[ios] - implement swipe support

What the topic says. Using native ios recognizer (i can allow pan and swipe recognizer at the same time - in the swipe recognizer i ask if the control wants that swipe recognized - if so - fire the message).

Works like a charme in slideshow. But as written in my e-mail there are some messages missing (ACTION_GESTURE_END) - which breaks the rotate/snap back feature. We have to clearup who is supposed to call this handler (imo - its not me - i fire the rotation handler and this should fire gesture_start, rotate, gesture_end - but you know better what would be right ;) ).