'Cancel' for PromiseKit --

    * Delete CancellableGuarantee and all its usages
    * In PromiseKit Core: instead of using additional functions and methods with the 'CC' suffix, created a new 'cancellable' function to wrap any Promise or Guarantee
    * In the extensions: Rename methods with 'CC' suffix to 'cancellable' prefix (may revisit this)
    * Fix the CancellableCatchable 'recover' methods to properly handle cancellation errors
    * Added an 'afterTask' property to Guarantee, to keep track of the task for calls to 'after'. This way the timer can be appropriately cancelled if the returned Guarantee is passed to the new 'cancellable' function. (may revisit this)
    * Update all cancellable tests for the cancellable API changes

Author: dougzilla32

Sources/UIViewPropertyAnimator+Promise.swift

@@ -25,7 +25,7 @@ extension UIViewPropertyAnimator: CancellableTask {
         return (state == .inactive) && (fractionComplete < 1.0)
     }
 
-    public func startAnimationCC(_: PMKNamespacer) -> CancellablePromise<UIViewAnimatingPosition> {
+    public func cancellableStartAnimation(_: PMKNamespacer) -> CancellablePromise<UIViewAnimatingPosition> {
         return CancellablePromise(task: self) {
             addCompletion($0.fulfill)
             startAnimation()

Tests/TestUIViewPropertyAnimator.swift

@@ -31,7 +31,7 @@ extension UIViewPropertyAnimatorTests {
         let animator = UIViewPropertyAnimator(duration: 0.1, curve: .easeIn, animations: { [weak self] in
             ex1.fulfill()
         })
-        let p = animator.startAnimationCC(.promise).done { _ in
+        let p = animator.cancellableStartAnimation(.promise).done { _ in
             XCTFail()
         }.catch(policy: .allErrors) { error in
             error.isCancelled ? ex2.fulfill() : XCTFail("Error: \(error)")