diff --git a/lib/async.js b/lib/async.js
index 2f52b6c..000b911 100644
--- a/lib/async.js
+++ b/lib/async.js
@@ -1,7 +1,7 @@
 /*global setImmediate: false, setTimeout: false, console: false */
 
 /**
- * https://raw.github.com/caolan/async/master/lib/async.js Feb 18, 2014
+ * async.js shim, based on https://raw.github.com/caolan/async/master/lib/async.js Feb 18, 2014
  * Used under MIT - https://github.com/caolan/async/blob/master/LICENSE
  */
 
@@ -9,76 +9,8 @@
 
     var async = {};
 
-    // global on the server, window in the browser
-    var root, previous_async;
+    // async.js functions used in Filer
 
-    root = this;
-    if (root != null) {
-      previous_async = root.async;
-    }
-
-    async.noConflict = function () {
-        root.async = previous_async;
-        return async;
-    };
-
-    function only_once(fn) {
-        var called = false;
-        return function() {
-            if (called) throw new Error("Callback was already called.");
-            called = true;
-            fn.apply(root, arguments);
-        }
-    }
-
-    //// cross-browser compatiblity functions ////
-
-    var _each = function (arr, iterator) {
-        if (arr.forEach) {
-            return arr.forEach(iterator);
-        }
-        for (var i = 0; i < arr.length; i += 1) {
-            iterator(arr[i], i, arr);
-        }
-    };
-
-    var _map = function (arr, iterator) {
-        if (arr.map) {
-            return arr.map(iterator);
-        }
-        var results = [];
-        _each(arr, function (x, i, a) {
-            results.push(iterator(x, i, a));
-        });
-        return results;
-    };
-
-    var _reduce = function (arr, iterator, memo) {
-        if (arr.reduce) {
-            return arr.reduce(iterator, memo);
-        }
-        _each(arr, function (x, i, a) {
-            memo = iterator(memo, x, i, a);
-        });
-        return memo;
-    };
-
-    var _keys = function (obj) {
-        if (Object.keys) {
-            return Object.keys(obj);
-        }
-        var keys = [];
-        for (var k in obj) {
-            if (obj.hasOwnProperty(k)) {
-                keys.push(k);
-            }
-        }
-        return keys;
-    };
-
-    //// exported async module functions ////
-
-    //// nextTick implementation with browser-compatible fallback ////
     if (typeof process === 'undefined' || !(process.nextTick)) {
         if (typeof setImmediate === 'function') {
             async.nextTick = function (fn) {
@@ -107,29 +39,6 @@
         }
     }
 
-    async.each = function (arr, iterator, callback) {
-        callback = callback || function () {};
-        if (!arr.length) {
-            return callback();
-        }
-        var completed = 0;
-        _each(arr, function (x) {
-            iterator(x, only_once(function (err) {
-                if (err) {
-                    callback(err);
-                    callback = function () {};
-                }
-                else {
-                    completed += 1;
-                    if (completed >= arr.length) {
-                        callback(null);
-                    }
-                }
-            }));
-        });
-    };
-    async.forEach = async.each;
-
     async.eachSeries = function (arr, iterator, callback) {
         callback = callback || function () {};
         if (!arr.length) {
@@ -145,7 +54,7 @@
                 else {
                     completed += 1;
                     if (completed >= arr.length) {
-                        callback(null);
+                        callback();
                     }
                     else {
                         iterate();
@@ -157,795 +66,6 @@
     };
     async.forEachSeries = async.eachSeries;
 
-    async.eachLimit = function (arr, limit, iterator, callback) {
-        var fn = _eachLimit(limit);
-        fn.apply(null, [arr, iterator, callback]);
-    };
-    async.forEachLimit = async.eachLimit;
-
-    var _eachLimit = function (limit) {
-
-        return function (arr, iterator, callback) {
-            callback = callback || function () {};
-            if (!arr.length || limit <= 0) {
-                return callback();
-            }
-            var completed = 0;
-            var started = 0;
-            var running = 0;
-
-            (function replenish () {
-                if (completed >= arr.length) {
-                    return callback();
-                }
-
-                while (running < limit && started < arr.length) {
-                    started += 1;
-                    running += 1;
-                    iterator(arr[started - 1], function (err) {
-                        if (err) {
-                            callback(err);
-                            callback = function () {};
-                        }
-                        else {
-                            completed += 1;
-                            running -= 1;
-                            if (completed >= arr.length) {
-                                callback();
-                            }
-                            else {
-                                replenish();
-                            }
-                        }
-                    });
-                }
-            })();
-        };
-    };
-
-
-    var doParallel = function (fn) {
-        return function () {
-            var args = Array.prototype.slice.call(arguments);
-            return fn.apply(null, [async.each].concat(args));
-        };
-    };
-    var doParallelLimit = function(limit, fn) {
-        return function () {
-            var args = Array.prototype.slice.call(arguments);
-            return fn.apply(null, [_eachLimit(limit)].concat(args));
-        };
-    };
-    var doSeries = function (fn) {
-        return function () {
-            var args = Array.prototype.slice.call(arguments);
-            return fn.apply(null, [async.eachSeries].concat(args));
-        };
-    };
-
-
-    var _asyncMap = function (eachfn, arr, iterator, callback) {
-        var results = [];
-        arr = _map(arr, function (x, i) {
-            return {index: i, value: x};
-        });
-        eachfn(arr, function (x, callback) {
-            iterator(x.value, function (err, v) {
-                results[x.index] = v;
-                callback(err);
-            });
-        }, function (err) {
-            callback(err, results);
-        });
-    };
-    async.map = doParallel(_asyncMap);
-    async.mapSeries = doSeries(_asyncMap);
-    async.mapLimit = function (arr, limit, iterator, callback) {
-        return _mapLimit(limit)(arr, iterator, callback);
-    };
-
-    var _mapLimit = function(limit) {
-        return doParallelLimit(limit, _asyncMap);
-    };
-
-    // reduce only has a series version, as doing reduce in parallel won't
-    // work in many situations.
-    async.reduce = function (arr, memo, iterator, callback) {
-        async.eachSeries(arr, function (x, callback) {
-            iterator(memo, x, function (err, v) {
-                memo = v;
-                callback(err);
-            });
-        }, function (err) {
-            callback(err, memo);
-        });
-    };
-    // inject alias
-    async.inject = async.reduce;
-    // foldl alias
-    async.foldl = async.reduce;
-
-    async.reduceRight = function (arr, memo, iterator, callback) {
-        var reversed = _map(arr, function (x) {
-            return x;
-        }).reverse();
-        async.reduce(reversed, memo, iterator, callback);
-    };
-    // foldr alias
-    async.foldr = async.reduceRight;
-
-    var _filter = function (eachfn, arr, iterator, callback) {
-        var results = [];
-        arr = _map(arr, function (x, i) {
-            return {index: i, value: x};
-        });
-        eachfn(arr, function (x, callback) {
-            iterator(x.value, function (v) {
-                if (v) {
-                    results.push(x);
-                }
-                callback();
-            });
-        }, function (err) {
-            callback(_map(results.sort(function (a, b) {
-                return a.index - b.index;
-            }), function (x) {
-                return x.value;
-            }));
-        });
-    };
-    async.filter = doParallel(_filter);
-    async.filterSeries = doSeries(_filter);
-    // select alias
-    async.select = async.filter;
-    async.selectSeries = async.filterSeries;
-
-    var _reject = function (eachfn, arr, iterator, callback) {
-        var results = [];
-        arr = _map(arr, function (x, i) {
-            return {index: i, value: x};
-        });
-        eachfn(arr, function (x, callback) {
-            iterator(x.value, function (v) {
-                if (!v) {
-                    results.push(x);
-                }
-                callback();
-            });
-        }, function (err) {
-            callback(_map(results.sort(function (a, b) {
-                return a.index - b.index;
-            }), function (x) {
-                return x.value;
-            }));
-        });
-    };
-    async.reject = doParallel(_reject);
-    async.rejectSeries = doSeries(_reject);
-
-    var _detect = function (eachfn, arr, iterator, main_callback) {
-        eachfn(arr, function (x, callback) {
-            iterator(x, function (result) {
-                if (result) {
-                    main_callback(x);
-                    main_callback = function () {};
-                }
-                else {
-                    callback();
-                }
-            });
-        }, function (err) {
-            main_callback();
-        });
-    };
-    async.detect = doParallel(_detect);
-    async.detectSeries = doSeries(_detect);
-
-    async.some = function (arr, iterator, main_callback) {
-        async.each(arr, function (x, callback) {
-            iterator(x, function (v) {
-                if (v) {
-                    main_callback(true);
-                    main_callback = function () {};
-                }
-                callback();
-            });
-        }, function (err) {
-            main_callback(false);
-        });
-    };
-    // any alias
-    async.any = async.some;
-
-    async.every = function (arr, iterator, main_callback) {
-        async.each(arr, function (x, callback) {
-            iterator(x, function (v) {
-                if (!v) {
-                    main_callback(false);
-                    main_callback = function () {};
-                }
-                callback();
-            });
-        }, function (err) {
-            main_callback(true);
-        });
-    };
-    // all alias
-    async.all = async.every;
-
-    async.sortBy = function (arr, iterator, callback) {
-        async.map(arr, function (x, callback) {
-            iterator(x, function (err, criteria) {
-                if (err) {
-                    callback(err);
-                }
-                else {
-                    callback(null, {value: x, criteria: criteria});
-                }
-            });
-        }, function (err, results) {
-            if (err) {
-                return callback(err);
-            }
-            else {
-                var fn = function (left, right) {
-                    var a = left.criteria, b = right.criteria;
-                    return a < b ? -1 : a > b ? 1 : 0;
-                };
-                callback(null, _map(results.sort(fn), function (x) {
-                    return x.value;
-                }));
-            }
-        });
-    };
-
-    async.auto = function (tasks, callback) {
-        callback = callback || function () {};
-        var keys = _keys(tasks);
-        if (!keys.length) {
-            return callback(null);
-        }
-
-        var results = {};
-
-        var listeners = [];
-        var addListener = function (fn) {
-            listeners.unshift(fn);
-        };
-        var removeListener = function (fn) {
-            for (var i = 0; i < listeners.length; i += 1) {
-                if (listeners[i] === fn) {
-                    listeners.splice(i, 1);
-                    return;
-                }
-            }
-        };
-        var taskComplete = function () {
-            _each(listeners.slice(0), function (fn) {
-                fn();
-            });
-        };
-
-        addListener(function () {
-            if (_keys(results).length === keys.length) {
-                callback(null, results);
-                callback = function () {};
-            }
-        });
-
-        _each(keys, function (k) {
-            var task = (tasks[k] instanceof Function) ? [tasks[k]]: tasks[k];
-            var taskCallback = function (err) {
-                var args = Array.prototype.slice.call(arguments, 1);
-                if (args.length <= 1) {
-                    args = args[0];
-                }
-                if (err) {
-                    var safeResults = {};
-                    _each(_keys(results), function(rkey) {
-                        safeResults[rkey] = results[rkey];
-                    });
-                    safeResults[k] = args;
-                    callback(err, safeResults);
-                    // stop subsequent errors hitting callback multiple times
-                    callback = function () {};
-                }
-                else {
-                    results[k] = args;
-                    async.setImmediate(taskComplete);
-                }
-            };
-            var requires = task.slice(0, Math.abs(task.length - 1)) || [];
-            var ready = function () {
-                return _reduce(requires, function (a, x) {
-                    return (a && results.hasOwnProperty(x));
-                }, true) && !results.hasOwnProperty(k);
-            };
-            if (ready()) {
-                task[task.length - 1](taskCallback, results);
-            }
-            else {
-                var listener = function () {
-                    if (ready()) {
-                        removeListener(listener);
-                        task[task.length - 1](taskCallback, results);
-                    }
-                };
-                addListener(listener);
-            }
-        });
-    };
-
-    async.waterfall = function (tasks, callback) {
-        callback = callback || function () {};
-        if (tasks.constructor !== Array) {
-          var err = new Error('First argument to waterfall must be an array of functions');
-          return callback(err);
-        }
-        if (!tasks.length) {
-            return callback();
-        }
-        var wrapIterator = function (iterator) {
-            return function (err) {
-                if (err) {
-                    callback.apply(null, arguments);
-                    callback = function () {};
-                }
-                else {
-                    var args = Array.prototype.slice.call(arguments, 1);
-                    var next = iterator.next();
-                    if (next) {
-                        args.push(wrapIterator(next));
-                    }
-                    else {
-                        args.push(callback);
-                    }
-                    async.setImmediate(function () {
-                        iterator.apply(null, args);
-                    });
-                }
-            };
-        };
-        wrapIterator(async.iterator(tasks))();
-    };
-
-    var _parallel = function(eachfn, tasks, callback) {
-        callback = callback || function () {};
-        if (tasks.constructor === Array) {
-            eachfn.map(tasks, function (fn, callback) {
-                if (fn) {
-                    fn(function (err) {
-                        var args = Array.prototype.slice.call(arguments, 1);
-                        if (args.length <= 1) {
-                            args = args[0];
-                        }
-                        callback.call(null, err, args);
-                    });
-                }
-            }, callback);
-        }
-        else {
-            var results = {};
-            eachfn.each(_keys(tasks), function (k, callback) {
-                tasks[k](function (err) {
-                    var args = Array.prototype.slice.call(arguments, 1);
-                    if (args.length <= 1) {
-                        args = args[0];
-                    }
-                    results[k] = args;
-                    callback(err);
-                });
-            }, function (err) {
-                callback(err, results);
-            });
-        }
-    };
-
-    async.parallel = function (tasks, callback) {
-        _parallel({ map: async.map, each: async.each }, tasks, callback);
-    };
-
-    async.parallelLimit = function(tasks, limit, callback) {
-        _parallel({ map: _mapLimit(limit), each: _eachLimit(limit) }, tasks, callback);
-    };
-
-    async.series = function (tasks, callback) {
-        callback = callback || function () {};
-        if (tasks.constructor === Array) {
-            async.mapSeries(tasks, function (fn, callback) {
-                if (fn) {
-                    fn(function (err) {
-                        var args = Array.prototype.slice.call(arguments, 1);
-                        if (args.length <= 1) {
-                            args = args[0];
-                        }
-                        callback.call(null, err, args);
-                    });
-                }
-            }, callback);
-        }
-        else {
-            var results = {};
-            async.eachSeries(_keys(tasks), function (k, callback) {
-                tasks[k](function (err) {
-                    var args = Array.prototype.slice.call(arguments, 1);
-                    if (args.length <= 1) {
-                        args = args[0];
-                    }
-                    results[k] = args;
-                    callback(err);
-                });
-            }, function (err) {
-                callback(err, results);
-            });
-        }
-    };
-
-    async.iterator = function (tasks) {
-        var makeCallback = function (index) {
-            var fn = function () {
-                if (tasks.length) {
-                    tasks[index].apply(null, arguments);
-                }
-                return fn.next();
-            };
-            fn.next = function () {
-                return (index < tasks.length - 1) ? makeCallback(index + 1): null;
-            };
-            return fn;
-        };
-        return makeCallback(0);
-    };
-
-    async.apply = function (fn) {
-        var args = Array.prototype.slice.call(arguments, 1);
-        return function () {
-            return fn.apply(
-                null, args.concat(Array.prototype.slice.call(arguments))
-            );
-        };
-    };
-
-    var _concat = function (eachfn, arr, fn, callback) {
-        var r = [];
-        eachfn(arr, function (x, cb) {
-            fn(x, function (err, y) {
-                r = r.concat(y || []);
-                cb(err);
-            });
-        }, function (err) {
-            callback(err, r);
-        });
-    };
-    async.concat = doParallel(_concat);
-    async.concatSeries = doSeries(_concat);
-
-    async.whilst = function (test, iterator, callback) {
-        if (test()) {
-            iterator(function (err) {
-                if (err) {
-                    return callback(err);
-                }
-                async.whilst(test, iterator, callback);
-            });
-        }
-        else {
-            callback();
-        }
-    };
-
-    async.doWhilst = function (iterator, test, callback) {
-        iterator(function (err) {
-            if (err) {
-                return callback(err);
-            }
-            if (test()) {
-                async.doWhilst(iterator, test, callback);
-            }
-            else {
-                callback();
-            }
-        });
-    };
-
-    async.until = function (test, iterator, callback) {
-        if (!test()) {
-            iterator(function (err) {
-                if (err) {
-                    return callback(err);
-                }
-                async.until(test, iterator, callback);
-            });
-        }
-        else {
-            callback();
-        }
-    };
-
-    async.doUntil = function (iterator, test, callback) {
-        iterator(function (err) {
-            if (err) {
-                return callback(err);
-            }
-            if (!test()) {
-                async.doUntil(iterator, test, callback);
-            }
-            else {
-                callback();
-            }
-        });
-    };
-
-    async.queue = function (worker, concurrency) {
-        if (concurrency === undefined) {
-            concurrency = 1;
-        }
-        function _insert(q, data, pos, callback) {
-          if(data.constructor !== Array) {
-              data = [data];
-          }
-          _each(data, function(task) {
-              var item = {
-                  data: task,
-                  callback: typeof callback === 'function' ? callback : null
-              };
-
-              if (pos) {
-                q.tasks.unshift(item);
-              } else {
-                q.tasks.push(item);
-              }
-
-              if (q.saturated && q.tasks.length === concurrency) {
-                  q.saturated();
-              }
-              async.setImmediate(q.process);
-          });
-        }
-
-        var workers = 0;
-        var q = {
-            tasks: [],
-            concurrency: concurrency,
-            saturated: null,
-            empty: null,
-            drain: null,
-            push: function (data, callback) {
-              _insert(q, data, false, callback);
-            },
-            unshift: function (data, callback) {
-              _insert(q, data, true, callback);
-            },
-            process: function () {
-                if (workers < q.concurrency && q.tasks.length) {
-                    var task = q.tasks.shift();
-                    if (q.empty && q.tasks.length === 0) {
-                        q.empty();
-                    }
-                    workers += 1;
-                    var next = function () {
-                        workers -= 1;
-                        if (task.callback) {
-                            task.callback.apply(task, arguments);
-                        }
-                        if (q.drain && q.tasks.length + workers === 0) {
-                            q.drain();
-                        }
-                        q.process();
-                    };
-                    var cb = only_once(next);
-                    worker(task.data, cb);
-                }
-            },
-            length: function () {
-                return q.tasks.length;
-            },
-            running: function () {
-                return workers;
-            }
-        };
-        return q;
-    };
-
-    async.cargo = function (worker, payload) {
-        var working     = false,
-            tasks       = [];
-
-        var cargo = {
-            tasks: tasks,
-            payload: payload,
-            saturated: null,
-            empty: null,
-            drain: null,
-            push: function (data, callback) {
-                if(data.constructor !== Array) {
-                    data = [data];
-                }
-                _each(data, function(task) {
-                    tasks.push({
-                        data: task,
-                        callback: typeof callback === 'function' ? callback : null
-                    });
-                    if (cargo.saturated && tasks.length === payload) {
-                        cargo.saturated();
-                    }
-                });
-                async.setImmediate(cargo.process);
-            },
-            process: function process() {
-                if (working) return;
-                if (tasks.length === 0) {
-                    if(cargo.drain) cargo.drain();
-                    return;
-                }
-
-                var ts = typeof payload === 'number'
-                            ? tasks.splice(0, payload)
-                            : tasks.splice(0);
-
-                var ds = _map(ts, function (task) {
-                    return task.data;
-                });
-
-                if(cargo.empty) cargo.empty();
-                working = true;
-                worker(ds, function () {
-                    working = false;
-
-                    var args = arguments;
-                    _each(ts, function (data) {
-                        if (data.callback) {
-                            data.callback.apply(null, args);
-                        }
-                    });
-
-                    process();
-                });
-            },
-            length: function () {
-                return tasks.length;
-            },
-            running: function () {
-                return working;
-            }
-        };
-        return cargo;
-    };
-
-    var _console_fn = function (name) {
-        return function (fn) {
-            var args = Array.prototype.slice.call(arguments, 1);
-            fn.apply(null, args.concat([function (err) {
-                var args = Array.prototype.slice.call(arguments, 1);
-                if (typeof console !== 'undefined') {
-                    if (err) {
-                        if (console.error) {
-                            console.error(err);
-                        }
-                    }
-                    else if (console[name]) {
-                        _each(args, function (x) {
-                            console[name](x);
-                        });
-                    }
-                }
-            }]));
-        };
-    };
-    async.log = _console_fn('log');
-    async.dir = _console_fn('dir');
-    /*async.info = _console_fn('info');
-    async.warn = _console_fn('warn');
-    async.error = _console_fn('error');*/
-
-    async.memoize = function (fn, hasher) {
-        var memo = {};
-        var queues = {};
-        hasher = hasher || function (x) {
-            return x;
-        };
-        var memoized = function () {
-            var args = Array.prototype.slice.call(arguments);
-            var callback = args.pop();
-            var key = hasher.apply(null, args);
-            if (key in memo) {
-                callback.apply(null, memo[key]);
-            }
-            else if (key in queues) {
-                queues[key].push(callback);
-            }
-            else {
-                queues[key] = [callback];
-                fn.apply(null, args.concat([function () {
-                    memo[key] = arguments;
-                    var q = queues[key];
-                    delete queues[key];
-                    for (var i = 0, l = q.length; i < l; i++) {
-                      q[i].apply(null, arguments);
-                    }
-                }]));
-            }
-        };
-        memoized.memo = memo;
-        memoized.unmemoized = fn;
-        return memoized;
-    };
-
-    async.unmemoize = function (fn) {
-      return function () {
-        return (fn.unmemoized || fn).apply(null, arguments);
-      };
-    };
-
-    async.times = function (count, iterator, callback) {
-        var counter = [];
-        for (var i = 0; i < count; i++) {
-            counter.push(i);
-        }
-        return async.map(counter, iterator, callback);
-    };
-
-    async.timesSeries = function (count, iterator, callback) {
-        var counter = [];
-        for (var i = 0; i < count; i++) {
-            counter.push(i);
-        }
-        return async.mapSeries(counter, iterator, callback);
-    };
-
-    async.compose = function (/* functions... */) {
-        var fns = Array.prototype.reverse.call(arguments);
-        return function () {
-            var that = this;
-            var args = Array.prototype.slice.call(arguments);
-            var callback = args.pop();
-            async.reduce(fns, args, function (newargs, fn, cb) {
-                fn.apply(that, newargs.concat([function () {
-                    var err = arguments[0];
-                    var nextargs = Array.prototype.slice.call(arguments, 1);
-                    cb(err, nextargs);
-                }]))
-            },
-            function (err, results) {
-                callback.apply(that, [err].concat(results));
-            });
-        };
-    };
-
-    var _applyEach = function (eachfn, fns /*args...*/) {
-        var go = function () {
-            var that = this;
-            var args = Array.prototype.slice.call(arguments);
-            var callback = args.pop();
-            return eachfn(fns, function (fn, cb) {
-                fn.apply(that, args.concat([cb]));
-            },
-            callback);
-        };
-        if (arguments.length > 2) {
-            var args = Array.prototype.slice.call(arguments, 2);
-            return go.apply(this, args);
-        }
-        else {
-            return go;
-        }
-    };
-    async.applyEach = doParallel(_applyEach);
-    async.applyEachSeries = doSeries(_applyEach);
-
-    async.forever = function (fn, callback) {
-        function next(err) {
-            if (err) {
-                if (callback) {
-                    return callback(err);
-                }
-                throw err;
-            }
-            fn(next);
-        }
-        next();
-    };
-
     // AMD / RequireJS
     if (typeof define !== 'undefined' && define.amd) {
         define([], function () {