Add component.json

Add a component.json file for package management and installation via [Component](http://github.com/component/component) and help with some of the other systems out there (Bower, Yeoman, etc). This fixes #756.

Once this is available, it's possible to run:
```bash
$ component install FortAwesome/Font-Awesome
$ component build
$ ls build
build.css  build.js  Font-Awesome
```