offline mission planning settings

more conversion stuff

some fixes and added area unit drop down

Conflicts:
	src/MissionEditor/MissionItemStatus.qml

removed comment

finish unit conversion

correcting typos

This is all going away in 3.1 so don’t want to spend time fixing broken
font sizing

Too buggy to leave it in for 3.0 release

Height will shrink to fit small text heights

- Offline maps new set defaults to default map type
- Plan/Fly views use MapScale control

Android done.

UI Tweaks for all mobile platforms.

* PX4: Deal properly with optional components

* RC map UI: Offer better defaults and user guidance

Actually, changed so showDialog figures out on its own if it should use available height or full parent height. The variable is now set by the main window, which controls which view is being shown.
I commented off some code in ParameterEditorDialog.qml as it is not properly handling the dialog and causing it to get "stuck".