Added bower.json

Hey!

First, thanks for this amazing library. It's been really useful for the project I'm working on. 

My motivation to send this PR was that I'm using bower to manage the dependencies and I didn't want to manage its dependencies manually. This was requested a long time ago as you can see at #50.

I extracted most of the content from package.json and created a bower.json.

After accepting, it will be necessary to release a new version (1.0.5) because bower download the latest version by default. 1.0.4 doesn't have the bower.json file, so...

Please feel free to suggest modifications so we can move forward.

Best,
Vítor Avelino.