Added angle conversion testing, added battery settings option, added option to set MAVLink ID of groundstation

Added right-click option to select MAV, ensured that waypoints get updated properly on switching MAV

Substantially bugfixed and improved deactivation/activation and persistence of widgets. A lot of testing of Google Earth view, only minor improvements

Fixed initial startup bugs, cleaned up the activation-deactivation of update timers. Added initial instructions for new users.

Working on QGraphicsView-based local waypoints interface supporting drag-and-drop, commented code, fixed Google Maps interface, added mouse and SpinBox zoom to HSIWidget, fixed MAV-based coloring and stylesheets - MEGA COMMIT

Improved speed by preventing update of UASView on every vehicle state change, view is now bound to 10 Hz update timer