Mavlink spec changed

Move set camera photo mode to be first item

Adding mux GStreamer plugin libraries to Android (to enable video recording on Android)
Adding an option to limit the amount to disk used for saving videos
Adding an option to show/hide the REC button (allowing plugins to handle the recording in their own way)
Adding simple frame grab to file

The ardupilot parameter meta data generator will generate dups when the
parameter is in ifdef'ed code