* (feat) gas oracle support
* (refactor) make a separate module | fix clippy warning
* add gas oracle to client using dynamic dispatch
* fix doc build in multicall module
* gas oracle returns U256
* support gas price fetching from client
* avoid querying for unsupported gas categories
* changes based on PR review
* add support for gasnow API, refactor gwei to wei
Rohit Narurkar