[eslint-config] Ability to use in pure JavaScript projects

[rakleed]

Summary

I would like to use the config in a project without TypeScript, as it has useful rules regardless of the presence/absence of TypeScript.

Details

By default you only look at ts files and tsconfig.json, although js projects use jsconfig.json:

rushstack/eslint/eslint-config/profile/_common.js

Lines 213 to 218 in 871e700

	files: ['*.ts', '*.tsx'],
	parser: '@typescript-eslint/parser',
	parserOptions: {
	// The "project" path is resolved relative to parserOptions.tsconfigRootDir.
	// Your local .eslintrc.js must specify that parserOptions.tsconfigRootDir=__dirname.
	project: './tsconfig.json',

It would be convenient if you made a separate config for JS projects, where these features would be taken into account.

Standard questions

Question	Answer
@rushstack/eslint-config version?	4.0.2
Operating system?	N/A
Would you consider contributing a PR?	No
TypeScript compiler version?	N/A
Node.js version (node -v)?	N/A

[iclanton]

We'd probably take this change, but all of our projects are in TypeScript, and TypeScript is the Rushstack recommended language, so we probably wouldn't put this change together ourselves. If someone else wants to take this on, go for it!