* First working version of eslint enabled with gulp
* Tryout of eslint with graph3d files
* Cleanup of gulp and eslint files.
* Completed test by linting graph3d
* Disable travis linting for now
* Remove global cmd param from .travis.yml
* First working version of new class DataGroup.
* Adjustments for review - done all points except last
* DRY distinct values, clean up sort code
* Added missing @param's to comments in DataGroup