Refactor

__Reviewers__:

- [ ] @jgchristopher
- [ ] @andymoon
- [ ] @doug-martin

This refactor separates thumbs into multiple, testable files. A new build step using grunt-preprocess will concat all the files into a single file, for distribution and minification. I also added a LICENSE file, and added the license comments to the top of the file

## Testing

Test the files with jasmine in phantom by running `grunt test`

## building

To build the concatenated and minified versions of thumbs, run `grunt build`, or simply run `grunt`