Rework ArduPilot Airfame setup page

Smart RTL support

Add support for ESC Calibration

Add support for geofence return point. Also fixed a bunch of bugs in geofence and rally point support.

More work on no serial port ifdef

Fix no serial and android builds

Check for CubeBlack service bulletin

Fix incorrect isManualCamera logic

Fix initialization

Pattern Preset support

Use consistent Altitude Mode labeling

Use new extraUnitField

Show extra unit in small font

Reduce space between graphic and text

Use standard Altitude Mode labeling

Add new file

Fix double tile download error reporting

Prevent double reporting of tile download errors

Offline Maps: Allow custom build settings overrides

Object ownership handled by SettingsGroup base class

Add support for ArduRover MockLink

Add FOLLOW flight mode

Change-Id: I80acc497ef8fc574f64b181a8d276c5b00d4e057

Heading: Switch from Radians to Degrees

Work around quirkiness with ArduPilot and LOITER_* NaN handling on heading.

No camera commands for ArduPilot

BUGFIX: When scanning from the top the starting altitude shall be equal to the structure altitude.

Hack around ArduPilot problems with unsupported NaN in Loiter commands

Wildcard connect to all Hex boards