Cleanup and refactoring in relation to drag and drop

-> folder creation, adding to folders, reordering, switching pages
-> ensuring parity of dragEnter and dragExit in cell layouts and workspace
   (neither were consistently getting an even number of each)
-> actually enforced above with exceptions -- probably want to
   take these out, but maybe we can leave them in as warnings
-> fixed bug with mapping points to hotseat
-> fixes other bugs with drag and drop

Change-Id: I564568f810f2784d122ec6135012b67c2e8e7551

src/com/android/launcher2/AppsCustomizePagedView.java

@@ -737,7 +737,6 @@ public class AppsCustomizePagedView extends PagedViewWithDraggableItems implemen
      * @param target where the item was dragged to (can be null if the item was flung)
      */
     private void endDragging(View target, boolean isFlingToDelete, boolean success) {
-        mLauncher.getWorkspace().onDragStopped(success);
         if (isFlingToDelete || !success || (target != mLauncher.getWorkspace() &&
                 !(target instanceof DeleteDropTarget))) {
             // Exit spring loaded mode if we have not successfully dropped or have not handled the