ArduPilot for configurable mavlink stream rates

Add support for DEFINE replacement in FactMetaData enumString/Value json loading

Updating the currently used version of GStreamer

Fix capatilization

Fix layer heights

More work on Structure Scan rewrite

Bug fixes for Structure Scan. Also includes support for Entrance/Exit Alt.

Move position of HITL to bottom. Handle no SYS_HITL param.

Warn if SYS_HITL is set

Fix debug output

USe correct number of available channels

Add support for Start From Top/Bottom, plus more helpful stats

When starting up, if you start the GS before connecting the bluetooth joystick the QGC needs to be closed and restarted to get it to recognize the joystick

Store correct tile set counts for image and elevation sets.

Fix crappy font rendering on Windows

Use correct QT_TRANSLATE_NOOP to prevent crash

Default ROI altitude to 0

Show camera mode if plan contains it