Plus lots of other cleanup

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

- 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

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

QGCUASParamManager and friends are replaced by FactSystem

New version using QtQuick along with an experimental Map Background

Also removed partially implemented an incorrect getCommunicationStatus
api

Also many LinkManager API changes to further isolate all link
management inside LinkManager.

So this special casing is no longer needed

Plus a large number of other changes to allow for orderly shutdown of
objects without crashes or asserts. This is need for unit tests to
create/delete global state around every test.

This removes confusion as to whether you call UAS::requestParameters
(incorrect) or QGCUASParamManager::requestParameterList (correct) from
client code.

This is the Pixhawk research board, not the PX4 production board.

also adds AMSL output in ft

Fix HIL link reconnect issues due to missing threading flag usage, warn user about missing config and take him to config view if necessary

Fix HIL link reconnect issues due to missing threading flag usage, warn user about missing config and take him to config view if necessary

Most math and backend storage was floats anyways, so most of these changes just half the data copied during function calls without reducing precision.