JazzHands 2.0!

Updated to work better with AutoLayout with new types of constraint animations
Added a new IFTTTAnimatedPagingScrollViewController for quick-start AutoLayout-friendly animated paging scroll view animations.
Added new keepView:onPage and keepView:onPages methods for much more simplicity in animating view positions on paging scrollviews, and much easier AutoLayout-friendly scrollviews.
Updated Demo app to show how to create a fully AutoLayout-friendly paging animated scrollview, perfect for use with rotation or the new iOS9 Split Screen multitasking.
Changed to simpler syntax for adding keyframes
Updated to animate CGFloat times, to simplify keyframe times and work more smoothly on Retina displays.
Switched from a pre-generated array of interpolated animation values to interpolating at any point between keyframes on demand, for faster animation creation and far fewer allocations when adding keyframes.
Replaced IFTTTAngleAnimation with IFTTTRotationAnimation, which takes degrees instead of radians.
Fixed Transform animations to work together. Now IFTTTScaleAnimation, IFTTTRotationAnimation, and IFTTTTranslationAnimation can all be used on the same view without conflicting.
Increased unit test coverage.
Made IFTTTAnimation easy to subclass with your own custom animation types (see MyCustomAnimation in the Demo app for an example of how easy this is).
Added Interpolatable protocol to define how to interpolate between values of different types.

New Animations

Added IFTTTFillColorAnimation, IFTTTStrokeStartAnimation, and IFTTTStrokeEndAnimation - thanks @pNre!
Added IFTTTTextColorAnimation - thanks @revolter!