added bower json

First of all thanks for this cool lib!

It would be even nicer if I could directly install it from bower, so I added a bower.json. If you accept this pull request you will need to do the following things:

- change the license (I just guessed you use MIT)
- install [bower](http://bower.io/)
- register the package ``bower register taggle.js git@github.com:okcoker/taggle.js.git``
- (maybe move the taggle.js and taggle.min.js on root level, this seems to be best practice. If you want me to do this, just say a word ;) )