Fix JSHint Errors

Great work on this library, we use it for our [app](http://sproutsocial.com).

We've included some small changes based on [JSHint](http://www.jshint.com/install/) which we use in our build process.  Not sure you'll care, but if so, here is a PR for it.

The most controversial thing would be the way I handled the switch -> case fall throughs you had for focus/hover and enabled/disabled.  Personally, I don't have a problem with the way you did them, but JSHint does not have a way to turn that error off.

The rest should be little things like unnecessary semicolons and whitespace mixing.  There are a couple missing semicolons and bad unescaped regex characters.