New VehicleLinkManager implementation

Clean up references to MainRootWindow globals

PX4 multi-battery setup

Support unlimited compasses, plus all sort of other ui fixup

Fix logging

Move calibration methods to Vehicle

Unified photo/video control which works with mavlink cameras and just video stream

Add support for Json file string translations

App messages now use simple modal message dialogs. Vehicle messages continue to use non-modal popup.

Remove unused HIL code

Flight mode fix, cherry picked from master

Use consistent "Launch" naming

Disable closing app on last window close. This will close
the app on every widget spawned in QML that closes (MessageBox)

Advanced tuning hidden due to crash from Qt problem