development: added fade to MotionAnimation

Sources/iOS/KeyframeMotion.swift

@@ -63,7 +63,7 @@ extension Motion {
      */
 	public static func path(bezierPath: UIBezierPath, mode: AnimationRotationMode = .auto, duration: CFTimeInterval? = nil) -> CAKeyframeAnimation {
 		let animation = CAKeyframeAnimation()
-		animation.keyPath = AnimationKeyPath.position.rawValue
+		animation.keyPath = MotionAnimationKeyPath.position.rawValue
 		animation.path = bezierPath.cgPath
         animation.rotationMode = AnimationRotationModeToValue(mode: mode)
 		

Sources/iOS/PulseMotion.swift

@@ -146,13 +146,13 @@ extension PulseMotion {
         
         switch animation {
         case .centerWithBacking, .backing, .pointWithBacking, .tap:
-            bLayer.add(Motion.background(color: color.withAlphaComponent(opacity / 2), duration: duration), forKey: nil)
+            bLayer.motion(duration: duration, animations: .background(color: color.withAlphaComponent(opacity / 2)))
         default:break
         }
         
         switch animation {
         case .center, .centerWithBacking, .centerRadialBeyondBounds, .radialBeyondBounds, .point, .pointWithBacking:
-            pLayer.add(Motion.scale(by: 1, duration: duration), forKey: nil)
+            pLayer.motion(duration: duration, animations: .scale(by: 1))
         default:break
         }
         
@@ -182,16 +182,13 @@ extension PulseMotion {
             
             switch animation {
             case .centerWithBacking, .backing, .pointWithBacking, .tap:
-                bLayer.add(Motion.background(color: color.withAlphaComponent(0), duration: duration), forKey: nil)
+                bLayer.motion(duration: duration, animations: .background(color: color.withAlphaComponent(0)))
             default:break
             }
             
             switch animation {
             case .center, .centerWithBacking, .centerRadialBeyondBounds, .radialBeyondBounds, .point, .pointWithBacking:
-                pLayer.add(Motion.animate(group: [
-                    Motion.scale(by: .center == animation ? 1 : 1.325),
-                    Motion.background(color: color.withAlphaComponent(0))
-                ], duration: duration), forKey: nil)
+                pLayer.motion(duration: duration, animations: .scale(by: .center == animation ? 1 : 1.325), .background(color: color.withAlphaComponent(0)))
             default:break
             }