General cleanup and refactoring, added popup

This extension works significantly better as a popup, I think in the
future it would be nice to have an option to "pop out" of Chrome and
work more like a traditional application.
Style work and refactoring markup
Merge pull request #8 from tbranyen/more-cleanup

More cleanup
Launches the extension just like Chrome
Added the MIT license
Add initial firefox tests
Merge pull request #10 from tbranyen/firefox

Firefox extension support
Merge pull request #9 from tbranyen/license

Added the MIT license