Major rework to support terrain profile display and terrain collision reporting

Propagate opacity and interactive properties to mission items
Set opacity to 0.5 for items that are not part of the current
edit view

Out Survey polygons with KML save

Use new SplitIndicator control

New QGCDynamicObjectManager support

More work on direction arrows

Change entry/exit, use new MapLineArrow control

New base class control for Survey/Corridor

Only show full visuals when selected

Get rid of QGCView, QGCViewPanel and FactPanel. All messages and dialogs are now handled in the root window.

Adding missing qgcView to QGCMapPolygonVisuals instance in SurveyMapVisual.qml

Otherwise things go haywire when points are added