Remove missing support for QGCView fact missing overlays

ArduPIlot Follow Me setup

Get rid of QGCView, QGCViewPanel and FactPanel. All messages and dialogs are now handled in the root window.

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

If Facts are referenced from FactPanelController, we need to reference
count the AutoPilotPlugin such that it doesn’t get destroyed until
after the FactPanelController is destroyed.

More consistent with Qml usage pattern

Summary page is also the launching spot for the setup screens. No more
left hand set of buttons.