Code Style Cleanup - A Manageable Approach?

[ricksbrown]

ESLint generates too many warnings to be enabled as part of the core Grunt task. Fixing all of the warnings at once would create a huge review burden.

I suggest we turn ESLint on as part of the core grunt task BUT exclude every file explicitly.

Then the process would be:

1. Clean up an entire file.
2. Remove it from the ESLint excludes so it can never get "dirty" again.
3. Create a PR, wait for it to be reviewed and merged.
4. Start at Step 1 for the next file and so on until they are all clean.

@alice If you are happy with this proposal I can set up the excludes and clean up the first file.