Remove drag disabiling on mousemove

When using drag delay, the event is cancelled on a series of events, including `mousemove` which seems to be always fired on Chrome Android, even in cases when `touchmove` doesn't fire. This cause the drag to never commence when using the delay property. See SortableJS#981

Sortable.js

@@ -417,7 +417,6 @@
 					_on(ownerDocument, 'mouseup', _this._disableDelayedDrag);
 					_on(ownerDocument, 'touchend', _this._disableDelayedDrag);
 					_on(ownerDocument, 'touchcancel', _this._disableDelayedDrag);
-					_on(ownerDocument, 'mousemove', _this._disableDelayedDrag);
 					_on(ownerDocument, 'touchmove', _this._disableDelayedDrag);
 
 					_this._dragStartTimer = setTimeout(dragStartFn, options.delay);