This patch moves some of the utility library shaders into a common
directory and makes the necessary renames across shaders. Additionally,
material-specific transform functions were moved outside of math utils
into a separate transform_utils.glsl file.
This is needed in preparation for the viewport compositor, which will
make use of some of those utilities and will require all material
specific bit to be removed out of those files.
Reviewed By: fclem
Differential Revision: https://developer.blender.org/D14688
