- proper escaping of braces when passing JSON to python
- pass information if walberla was built with CUDA to pystencils
  to support apps that use GPU optionally

- information from CMake to codegen: double/float, OpenMP, ...

- one python file can now generate multiple source files

- Add generator files to targets to show them in VS solutions
- mark generated files as such in CMake

If you have access to the old closed source waLBerla repository, you may restore the complete history with the following command
git fetch git@i10git.cs.fau.de:software/walberla.git 'refs/replace/*:refs/replace/*'