New version using QtQuick along with an experimental Map Background

Also removed partially implemented an incorrect getCommunicationStatus
api

This signal passes the parameter type as well as param info

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.

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.

Enable RC calibration mode during RC calibration to tell vehicle to ignore stick inputs for that period

Altitude splitted to altitudeAMSL and altitudeRelative, speed splitted to airSpeed and groundSpeed. PrimaryFlightDisplay uses airSpeed for FW and groundSpeed for MC.

Replace 9 seperate valueChanged() signals with just 1, and remove the resultant tons of code duplication

Vastly improved the joystick documentation, removed some redundant/unnecessary code, and fixed a couple of small bugs. This code should be ready for live testing.

The default UAS.cc now lists available actions that it can be commanded. These are polled by the Joystick Configuration window for each joystick button so that they can be assigned to trigger this action. Button presses don't yet trigger these actions, nor are they stored and reloaded on UAS switch.

The UASInterface now defines a systemCanReverse() function for indicating if the UAS is capable of commanding a reverse thrust.

Partway through refactoring of UAS deletion. This is in order to actually support removing UASes from QGC, which is currently impossible.