Make AirPlay photo sharing works with iOS 7.1
No need to add randomisation to bonjour first registration
Improve AirPlay photosharing

Make the AirPlay photo sharing’s behavior closer to what an Apple TV does:
- Make the photo disappear whenever you exit the photo application
- Allows to play music while showing photos
- Improve transition between photos and videos
- Only make the photo disappear once video playback has started