Instead us a Toolbox concept which hangs off of QGCApplication

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

Passing parameters QVariantMap across C++ boundary was causing crashes
in Qt due to Qml array bugs. Referencing same Fact* across Qml boundary
in multiple QQuickWidgets caused jScript GC to crash.

Since this is generic Qml support not specific to FactSystem

- properties now hand off of main “autopilot” object in qml
- Added support for summary items through qml

Allows parameter access from QML among other things

Used for unit testing