Remove/comment off debug output pollution

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

Calling delete on a socket callback is not safe and this can crash
QGroundControl. Using deleteLater method from socket to perfom deletion.

And don't pass along message pointers

And fix broken file path to save video on windows

Other minor formatting and stability improvements