Fix for #3770, Zip improvement for #1526

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@30886 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e
* Better handling textures/not textured geometries
* Shader can use one normal for all vertices
* Shader : start triangulation of polygons (done for convex)

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@30887 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e