[chore] Create .eslintrc.js and update eslint related deps

[adityavohra7]

Updated eslint and some related deps. They still satisfy (I think?) the peer deps declared by eslint-config-react-app. I also changed .eslintrc to .eslintrc.js as it's treated with highest priority (and we could do any kind of logic in a JS file). Also, this version of eslint allows us to specify overrides, so we don't need the .eslintrc in the test/ folder anymore.

lint and test still seem to pass:

➜  redux git:(update_eslint_things) npm run lint

> [email protected] lint /Users/adityavohra7/Documents/Github/redux
> eslint src test build

➜  redux git:(update_eslint_things) echo $?
0
➜  redux git:(update_eslint_things) npm run test

> [email protected] test /Users/adityavohra7/Documents/Github/redux
> cross-env BABEL_ENV=commonjs jest

 PASS  test/typescript.spec.js
 PASS  test/createStore.spec.js
 PASS  test/combineReducers.spec.js
 PASS  test/applyMiddleware.spec.js
 PASS  test/bindActionCreators.spec.js
 PASS  test/utils/warning.spec.js
 PASS  test/compose.spec.js

Test Suites: 7 passed, 7 total
Tests:       69 passed, 69 total
Snapshots:   0 total
Time:        3.196s
Ran all test suites.
➜  redux git:(update_eslint_things) echo $?
0

Let me know what you think!

[adityavohra7]

Friendly bump! Let me know if there are any questions I can answer, or if I'm doing something horribly horribly wrong.

[timdorr]

Thanks, this is neat!

[adityavohra7]

@timdorr, awesome! Thanks for merging! Would you be open to a PR adding prettier?