REVIEW: 121504
Add function displaying the angles for the Measure Plugin in intuitive way
by Sergey Popov
Refactored header of the addplacemark\bookmark\addgroundoverlay dialogs
REVIEW: 121518
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
cosmetics
attributes--
split matrices in texture vertex shader
wip projection in shaders