Implement Custom Contract Interaction

[bh2smith]

PR #22 reveals a lot of abstraction that can be made out of this project. Much of the boiler plate code is unnecessary.

It would be amazing to implement a "custom" contract interaction

user runs exec --command CUSTOM

Then provides:

--contractAddress: str
--abi-file: Path [optional can be fetched]
--methodName: str
--functionArgs: list[str] (would need to be parsed into appropriate type)

We could also fetch the expected names from the ABI file and ask them to provide one at a time (by name).