When using FormatText() several times in same function, returned string is static and so, the same is returned, resulting in failures on shader loading.

Issue was related to vertex tangent attibutes not uploaded to GPU, a quick solution was implemented for new vertex attributes loading for already existing meshes... I don't like it specially but it will work for now.

Actually, that function should be redesigned...

Moved PBR material loading to example, right decision?