Rs_pbrt v0.4.3 implements FourierMaterial

By adding a new test scene (a VW Van) to the repository, where I collect those scenes, I triggered a lot of TODOs, which I documented in several issues ... the details are in the release notes:

Interesting (new) links in the documentation:

  1. FourierMaterial
  2. reflection (see FourierBSDF and FourierBSDFTable)
  3. interpolation
  4. floatfile (read_float_file)