Plus lots of other cleanup

- MultiVehicleManager is a Qml friendly replacement for UASManager
- Vehicle is a replacement for both UAS and AutoPilotPlugin

Switched to new. I’ve seen this before with other Qt classes and have
had to change the usage in the same way.

This makes unit test output easier to read

This makes unit test output easier to read

This function is called automatically when a QSettings object is destroyed,
so is rarely needed to be called explicitly.

There are still some cases where
a QSettings object is passed-by-reference, so there I left the sync() calls as
it's unclear how permanent those objects are and if they'd call sync() before
application shutdown

Subclass of QMessageBox which re-implements the static public
functions. There are two reasons for this:
1) The QMessageBox implementation on OSX does now show the title
string. This leads to message boxes which don't make much sense. So on
OSX we set title to text and text to informative text.
2) If parent is NULL, we set parent to MainWindow::instance. This
prevents message boxes which can go behind MainWindow

Map widget: make all connections that might suffer from multiple connect logic issues unique, found by Nyaruko

also adds AMSL output in ft

Not sure what qmake # escape is. So fixed the problem instead.

Altitude splitted to altitudeAMSL and altitudeRelative, speed splitted to airSpeed and groundSpeed. PrimaryFlightDisplay uses airSpeed for FW and groundSpeed for MC.

Add map type selector menu; use Bing maps by default; zoom to a more
human scale on Go Home

Add map type selector menu; use Bing maps by default; zoom to a more
human scale on Go Home

Removing UASes now returns the UI to an almost pristine state. This was done by altering the activeUASSet signal so that it can emit a NULL UAS. Crashes may still exist in autopilot-specific code.