This patch add the use of DRWShaderLibrary to EEVEE's
glsl codebase to reduce code complexity and duplication.
This then split bsdf_common_lib.glsl into multiple
sub library which are now shared with other engines.
The surface shader code is now more organised and
have its own files.
Also change default world to use a material nodetree
and make lookdev shader more clear.
More rewrite of closure_lit_lib is to come to reduce
glsl code amount the compiler has to digest.