Add Linting options

- Adds the latest Rockabox JSHint configuration file
- Adds the latest Rockabox JSCS configuration file
- Adds the latest Rockabox Editor config file for JS
- Sets the ``grunt-contrib-jshint`` and ``grunt-jscs`` to the version which is currently up-to-date and can use the config files
Merge pull request #1 from rockabox/nick/setup-for-linting

Adds Linting options