closure updated to use bower.

Hey guys, there wasn't much I could think of to do with this one. I created the component.json with just todomvc-common, since Closure's all buddy-buddy with Java.

Also, should component.json be pointing to todomvc-common `~0.1.2` or should I change it to `~0.1.3`?

Anything else I can do, let me know!