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

This can only come from the heartbeat

- FirmwarePlugin is the new place for code which is specific to
firmware flight stack
- FirmwarePlugin currently supports flight mode apis
- Modify code to use new FirmwarePlugin support

Also fixed case where UASMessageHandler reported errors but walking
list turned up no errors

Also restructured some toolbar positioning QML to handle resizing.

Added gaussian noise function.  Currently noise will not be added to measurements unless a user changes the initialization value and builds from source.

Added setter functions for HIL noise variances.  Researching methods to add zero mean gaussian random number before implementation