Conversation

@folkertvanheusden @OpenSCAD I think it would be a useful feature to uniqify all different texture values see in the file (if there is a somewhat finite amount) and then put them in a `declare` section with symbolic names at the top of the povray file to make it easy for the user to overwrite.

That way it is possible to play with different colors, reflectivity and other texture properties that are only available in povray.