Restore animation when releasing pinch

See Jake-Short#27

Author: skjiisa

Sources/ImageViewer/PinchToZoom.swift

@@ -69,10 +69,12 @@ class PinchZoomView: UIView {
             offset = CGSize(width: location.x - startLocation.x, height: location.y - startLocation.y)
 
         case .ended, .cancelled, .failed:
-            isPinching = false
-            scale = 1.0
-            anchor = .center
-            offset = .zero
+            withAnimation(.interactiveSpring()) {
+                isPinching = false
+                scale = 1.0
+                anchor = .center
+                offset = .zero
+            }
         default:
             break
         }