Mavlink terrain protocol support

Integrate Create Plan overlay in File DropPanel

New Create Plan support

Fix initial load for Plan view

Fix AutoLoad not sending GeoFence or Rally Points to vehicle

Expose root plan keys

Cleaning up old vehicle manager and getting it ready to actually provide services for a vehicle (flight management)
Added submit flight plan
Added update flight plan
Disable flight features as these don't seem to be quite working (values must be initialized and validated before submission as backend doesn't validate and the objects don't initialize their members)

Split save mission to Json file in two so you have the option to saving it to a file or to a QByteArray Json blob.
Virtualize all camera functions to allow deeper access.

* Flight modes still not implemented. Waiting on message change.
* Also includes various cauterization of UI things which should not be
available on high latency link.

Signed-off-by: Patrick José Pereira <patrickelectric@gmail.com>

Update unit tests to catch this

This time to handle correctly updating plan/fly view when plan changes

Update the user model to a single controller instead of multiple