Add bower support

Using this, you'll type "bower install amplitude" and bam! Better yet,
you can include it in your dependencies.

After you merge this, you'll want to tag a release (I picked 0.1.0, feel free to change it in bower.json) in Git, and then run "bower register amplitude https://github.com/521dimensions/amplitudejs.git" (as noted in http://bower.io/docs/creating-packages/#register).