Handy for testing without a real board

* The "Simulation" option is now not selectable.
* If the link is a simulation, then you can't change it to a different link type.
* The OPAL option is not shown if support is not compiled in.
* Fix the buddy, tab order and accelerators in the GUI.

Still need to add uas connections. New osgwidget inherits from
qgraphicsview to expose more functionality to qt. Map3d.ui contains
the graphics view and some buttons. Currently runs yahoo_heightfield
by default. Make sure you run qgroundcontrol fromt the top dir or
it will seg fault, :-). I'll add some error handling soon.

Cleaned up and commented major code parts. Refactoring HDD and HSI widgets to support QGraphicsView drag-and-drop, tested multi-MAV support more intensely, currently adding the system coloring to all widgets