Carthage support

[jhurliman]

Surge is almost Carthage compatible. It looks like the only thing missing is marking the scheme for the Surge dynamic framework as "shared" in Xcode (then publishing a new release).

[alejandro-isaza]

My fork has Carthage support plus Swift 2.0: https://github.com/aleph7/Surge

[nicholascross]

👍 I would like to see carthage support added. The fork mentioned by @Aleph7 doesn't seem to support tvos (when running carthage update no tvos framework is built).

[rfdickerson]

I added a Cartfile to the project, but because we don't rely on any dependencies it remains empty. Let me know if this worked for you!