Support installation via Carthage

[rmccue]

I'm working on an app with the singular dependency of the Editor, which is loaded via CocoaPods. Because of the centralised nature of CocoaPods, there's a significant barrier to entry to working with the app when you're on a slow internet connection (as I found myself last month when in the middle of Slovakia).

Carthage is decentralised and generally seems like a better approach, but it only supports dynamic libs right now and doesn't work automatically with this repo. It'd be nice if that was possible. :)