Completely convert project to Tuist.

[MatyasKriz]

This has the added benefit of generating a consistent development environment.

The xcodeproj generation, CocoaPods integration, and opening the project is provided by the Makefile in the project, so that a simple make with CocoaPods and Tuist is enough.

TODO:

• [x] Remove Cuckoo-Workspace-X schemes Tuist generates for each platform which aren't valid and we have no need for them.
• [x] Add mock generation build phase to test targets.
• [x] Include generator as well?