- Colladawriter now writing matrices for node transformations as old solution did not work with CDummyTransformationSceneNode's.
- Colladawriter no longer create an extra node for the scenemanger as <visual_scene> has that job in Collada.
- Colladwriter no longer makes all Scenenodes children of ambient-light as that can be parallel on the same layer instead.
- Colladareader now creates the ambient-light correct instead of creating a point-light for it.

git-svn-id: svn://svn.code.sf.net/p/irrlicht/code/trunk@4267 dfc29bdd-3216-0410-991c-e03cc46cb475