Refactored PX4 radio config to work with both PX4 and APM

Windows OS doesn’t disconnect port when you pull plug on USB. This
caused all sorts of problems with previous logic. New logic handles
this correctly.

- Pervasive change to automatically connect to known board types
- Lots of additional changes along with this:
- More exposure of objects/properties to Qml
- Much restructuring in LinkManager and LinkManager clients

- Pervasive change to automatically connect to known board types
- Lots of additional changes along with this:
- More exposure of objects/properties to Qml
- Much restructuring in LinkManager and LinkManager clients

- Pervasive change to automatically connect to known board types
- Lots of additional changes along with this:
- More exposure of objects/properties to Qml
- Much restructuring in LinkManager and LinkManager clients

Also turn on MavlinkLogTest

Instead us a Toolbox concept which hangs off of QGCApplication

Too unstable for CI at the moment

Allows for signal count > 1

Also merged MissionController and MissionEditorController into single
MissionController implementation

This is in preparation for full Qml main window

Was failing due to large log output from incorrectly named
MockLinkLogVerbose.

- select active vehicle
- arm/disarm
- select flight mode

- fix bugs found by test
- Implemented Mock mission item protocol in

- 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.