Move away from the kludgy AZDrawingFunctions. Better UIImage helper.

Signed-off-by: Zachary Waldowski <zwaldowski@gmail.com>
Fix positioning of radial AZGradient.

Signed-off-by: Zachary Waldowski <zwaldowski@gmail.com>
Improve performance of AZGradientView.

Signed-off-by: Zachary Waldowski <zwaldowski@gmail.com>