add the functionality to erase the list of Waypoint widget (WaypointView) from the button of the WaypointList widget

add widget WaypointView to widget WaypointList when create a waypoint with mouse over the map

Major refactoring of the waypoint code. The new design fits the model-view-controller pattern better.

Major cleanup of MainWindow constructor. All widgets have now the visible property set to false on its constructor

UASWaypointManager now implements the protocol described in http://qgroundcontrol.org/waypoint_protocol

current status of the waypoints is transmitted, crashes due to a bug in waypointplanner - the crash has to be fixed