AirspaceManager is now exposed by QGroundControlQmlGlobal instead of Vehicle (available all the time)

* Also handles correct prioritization of high latency links

Plus various bug fixes from flight testing

Also remove custom gimbal support

And fixes they found

Maintain a list of address/port pairs instead of a address/port map.

Minor improvement to detection of stick recentering after calibration. Without this if you performed a calibration with deadband enabled but one of the deadbands at the end of the calibration was ~0 it would be very difficult to position the stick so that Qgroundcontrol considered the axis to be centered.

recentered after calibration.

Made it so that raw axis monitor indicators are narrow so that they don't obscure view of the deadzones.