Alsey Coleman Miller

Implement Core Animation layers and refactor view composition.

Also improve UIView animations (#16) implementation to use this new class.

Also `UITabBar` and if necessary the view transition methods (e.g. `viewWillAppear()`).

Depends on `UIView` animations #16.

Depends on `UIScrollView` #13

Implement View.clipsToBounds

2

Respect `View.clipsToBounds: Bool` in `Screen` for Silica drawing.

Only single line text rendering is working properly, implement multiline rendering.

Depends on #1

Switch to Pure Swift JSON parser, like SwiftyJSON https://github.com/colemancda/Jay

Add SwiftPM plugins for code generation. Remove current code generation code in `DarwinTests`. - [x] #144 - [ ] #145 - [ ] #146