Extract Lint Rules into Standalone Package

[kwelch]

The lint rules included in CRA are helpful for helping find potential bugs. It does so while not governing over code style.

I recommend these rules to be extracted and implemented in their own package to allow for use outside of CRA and to allow for community development of these rules.

[gaearon]

Yea, totally. Will do that after we land monorepo configuration PR.

[fson]

Implemented in #689.