Fix terrain NaN making it all the way to Planned Home altitude

Adding Airmap integration to QGC

# Conflicts:
#	src/Vehicle/Vehicle.cc

MAVLink Status

# Conflicts:
#	libs/mavlink/include/mavlink/v2.0

Fixed the core MAVLink receiver. Among other things, it wasn't accounting for fragmented messages.
Fixed code that monitors messages received (and lost)
Added a section within the MAVLink panel to show the current status (for the current vehicle)
Remove some old, unused exposed interfaces

Updating localization strings

Also fixing some c++ errors within commented off code as the localization engine was getting confused by it.

Limit all queries to areas smaller than 500km^2. If an area of interest is greater, clip to 500km^2 centered on current ROI's center.
Removed the identifier "Airmap" from error messages coming from Airmap.
Added a clipping function to QGCGeoBoundingCube (clip polygon to given area)

[QmlObjectListModel] fix list insert

Fixes https://github.com/mavlink/qgroundcontrol/issues/6770

I have no idea how this was building elsewhere at all.

# Conflicts:
#	src/Vehicle/Vehicle.cc
#	src/api/QGCCorePlugin.cc

Custom Plan Save/Load

Limit pixel density fudge to Android only

Expose root plan keys

Dealing with pixel density on Windows and iOS

Allow a plugin to override iOS build settings.

If APM firmware type is disabled, skip all the firmware uploading

Change Log: Add initial 3.5 entries

Add initial 3.5 entries

Add change log