* Make MainToolbarIndicators reusable by other views
* Change to font based ratio sizing

Shows horizontal/vertical scroll indicators

Made QGCCorePlugin derive from QGCToolBox and expose everything through the same mechanism as everything else.

Conflicts:
	src/MissionManager/GeoFenceController.cc

This makes it available on mobile builds

_finalize methods need information which is not available if all you
have is a mavlink_message_t

-fixes #4035

Move battery.percentRemainingAnnounce to Qml Global

The static Fact was causes problems with Qml

Also updated some docs

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

Rewrote editor to be performant enough to support typedown