Fix support for single vehicle coming and going

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

No signing support yet

_finalize methods need information which is not available if all you
have is a mavlink_message_t

Also, changed an if(true) then true; else false; code

Signed-off-by: Tomaz Canabrava <tomaz.canabrava@intel.com>

- 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

Instead us a Toolbox concept which hangs off of QGCApplication

This is in preparation for full Qml main window

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

Added the possibilty to see only one UAS at the time with the drop down menu after clearing the view

Added support for stream rate config to MAVLink inspector. Allows to configure the update rate per message

cause: check for null pointer had no effect (static memory)
solution: fill mavlink messages (and thus) message type with 0xff. this patch assumes that message ID 0xff is never used
positiv side effect: qgroundcontrol uses 2% less cpu on my machine (eeepc)