Marble: Add a drawOrder KML tag handler
completed by: Illya Kovalevskyy
mentors: Torsten Rahn, René Küttner, Dennis Nienhüser
Implement support for the drawOrder KML element:
- Add a kml handler for drawOrder. Have it check the parent to be an Overlay and set its drawOrder value
- Adjust TestScreenOverlay.cpp and TestGroundOverlay.cpp to test for different drawOrder values
References:
- https://developers.google.com/kml/documentation/kmlreference#draworder
- http://marble.kde.org/kml-guide.php