Access DebugMenu from anywhere in the app

With global window gestures, it's very important to allow all other gestures to behave normally. There are no scrollviews in the demo app, but as it is right now, if you try to scroll a scroll view or do anything that requires a gesture in the app itself, touches will be laggy because the event delivery chain will wait to confirm that another gesture is valid until it is sure that the window gesture is not going to be recognized.

To fix this, you need to have `RZDebugMenu` implement the gesture delegate and return `YES` for `gestureRecognizer:shouldRecognizeSimultaneouslyWithGestureRecognizer:`.