Shader parameters from material skills

The title says it all: Currently the library shaders all use entity skill 41-44 for their parameters, but it would be better if material skills were used. This way shader parameters can be set for all entities, and not for single entities only. Even better, the shaders could use skill 41-44 but use the material skills when the entity skills are zero.

This makes sense and I'll put it on my list.