* feat: allow encoding/decoding function data
* feat: allow decoding event data
* feat: human readable abi
inspired from https://blog.ricmoo.com/human-readable-contract-abis-in-ethers-js-141902f4d917
* test: add event / fn decoding tests
* chore: fix clippy
* feat(abigen): allow providing args in human readable format
* refactor: extract minimal features of Contract into BaseContract
* refactor: move BaseContract to own file
* chore: ensure celo test passes
* chore: fix clippy
Co-authored-by: Georgios Konstantopoulos <me@gakonst.com>