@zamiang(cc @gib): Refactor edit app + rich text editing

Sorry for the large diff. FWIW it's again a lot of shrinkwrap diff and mostly moving code around. This PR first breaks up the /edit/client, /edit/stylesheets, /edit/templates into a /components directory structure (kinda like what we do with the fair app in Force). As the React app grew I decided it would be better in the long run to break it up into it's individual components rather than let the single file grow in size.

The main new functionality added here is rich text editing using the mind blowingly awesome [Scribe](https://github.com/guardian/scribe) by The Guardian team. They use AMD modules which was kind of annoying to work around, but once I got through that it was pretty easy to integrate it into React's `componentDidUpdate` hook.

Finally I also refactored things a bit to be able to add sections in between each other.

![cap](https://cloud.githubusercontent.com/assets/555859/4728474/8273aacc-5976-11e4-870b-1e108d6fd681.gif)

Might be worth adding that as a comment. Definitely non-obvious (at least to me)