Trigger camera in instrument panel page

New QGCGroupBox control

Modified DropPanel cancel MouseArea creation

Previous mechanism was exposing possible bug in Qt which would prevent
clicks from work on ToolStrip buttons after cancel MouseArea was hidden.

Switch to Qt 5.8

Add Sub master to firmware options

QGCOptions: Remove deprecated methods

Control sizing on mobile

Allow setting the video streaming aspect ratio.

Fix indoorPalette overriding

More moves of settings to new support

DropPanel: Showing up under toolbar on short screens

Also correctly set implicitHeight on QGCTextField

QGCOptions: Remove deprecated methods

Replaced by new settings capability

Add Mixers tuning page

FixedWing Landing Pattern: More work on visuals

Handle videoSource changes correctly

Allow third-party flight mode overrides