Feature request: Add a feature to show that cells can be swiped

This would be nice to have some feature like the Facebook have to show newbie users that cell can be swiped. They just force a cell swipe control to jump a bit and make it obviously to the user that cells can be swiped.

Using these functions along with dispatch_after you could create that effect

func hideSwipeAnimated(animated: Bool)
func showSwipe(direction: MGSwipeDirection, animated: Bool)

I'll add some code in the readme about this