find QExtSerialPort library under ArchLinux
remove redundant namespace qualifier
ignore Qt Creator's CMakeLists.txt.user file
move placemark to center of ground overlay
cache onto own QPixmap rather than using QPixmapCache
introduce MarbleView
introduce MarbleGLView
introcude GlLayerInterface
clear depth buffer between layer rendering
TextureLayer
PlacemarkLayer
introduce triangulation algorithm for polygons

* taken from http://www.crystalspace3d.org/svnroot/crystal/CS/trunk/{include/csgeom/triangulate.h, libs/csgeom/triangulate.cpp}.
GeometryLayer
introduce GeoGraphicsScene::GlTile and use glDrawElements
adapt PlacemarkLayout
use shaders
GLRenderer