refractoring and clean up

[Cewein]

There is a lot of things in the path tracer as of now. We want to add data optimisation with a bvh and also add the Pixar BSDF with his own scene loader. but everthing is need to be clean before.

CPU code

we need to clean up every class and change the way everyting work, some name are not rigth and are missleading. there is even some unused classes (cf frame buffer) and maybe some ugly code. Since the BVH will take a lot of place and the scene loading too we need to improve everthing before.

Shader code

the shader is really heavy and the refractoring, and a #include. the #include will need a bit of parsing and testing.

please reference all the commit about the cleaning.

🧹 🧹 🧹

[Cewein]

it's done, the raytracer is now fully rewritten with less bloated code and easierr way to read the code