creating terrain in physx, copy it to osg

now working with non square tiles :-D
not able to fetch correct vertices from osg terrain... but maybe we will newer need this.
make it bigger, so the spheres won't get lost :-D
Merge remote-tracking branch 'origin/navigation_godmanipulator' into osgTerrainTest
create multiple tiles
fix tile id computation
usable config for testing
Merge remote-tracking branch 'origin/osgTerrainTest' into navigation_godmanipulator
set configs to generate small terrain at beginning