Remove CMake templating

[AntoinePrv]

Describe the problem or improvement suggested

Templating steup.py and doc/config.py with CMake makes it laborious to add new files and increase the barriers to contributing.

Describe the solution you would like

• Add the authors, version,... in files under about/ and read them separately from Python and CMake.
• Edit setup.py to find the shared library somewhere else?
• Change the installation instructions if needed

Describe alternatives you have considered

Move to scikit-build #37

Additional context