UIKit iOS 12.1 Beta 3 to GM API Differences

UIPencilInteraction.h

Added UIPencilPreferredAction

Added UIPencilPreferredActionIgnore

Added UIPencilPreferredActionSwitchEraser

Added UIPencilPreferredActionSwitchPrevious

Added UIPencilPreferredActionShowColorPalette

Added UIPencilInteraction

Added UIPencilInteraction.preferredTapAction

Added UIPencilInteraction.delegate

Added UIPencilInteraction.enabled

Added UIPencilInteractionDelegate

Added -[UIPencilInteractionDelegate pencilInteractionDidTap:]