Support solidity v0.7.x

[HenryNguyen5]

Description

Adds support for solidity 0.7.x in sol-compiler

Testing instructions

Run yarn build && yarn test within the sol-compiler directory

Types of changes

New feature Adds support for solidity 0.7.x in sol-compiler

Checklist:

• [x] Add tests to cover changes as needed.
• [x] Update documentation as needed.
• [x] Add new entries to the relevant CHANGELOG.jsons.

[HenryNguyen5]

Not too sure why CI is failing here, i built the package locally and linked it against https://github.com/smartcontractkit/chainlink/tree/develop/evm-contracts, which worked fine for compiling 0.4.x -> 0.7.x solidity contracts fine

[dorothy-zbornak]

Not too sure why CI is failing here, i built the package locally and linked it against https://github.com/smartcontractkit/chainlink/tree/develop/evm-contracts, which worked fine for compiling 0.4.x -> 0.7.x solidity contracts fine

Yeah it's just the solc registry timing out. I restarted it. :crossed_fingers:

[HenryNguyen5]

@dorothy-zbornak should be fixed up now!

[dorothy-zbornak]

Gonna merge this into my branch first to fix the annoying linter issues.