migrating to version 5

[j-faria]

I'm planning a new major release with very significant changes and (hopefully) improvements. This issue will keep track of the progress.

• [ ] merge v5 into beta (probably several times...) 1/?
• [ ] make the move from src to kima folders consistent
• [ ] "re-implement" all examples
• [ ] add new examples
• [ ] new models
• [ ] new interface between pykima and the C++ implementations of GPs and (probably) distributions
• [ ] update documentation
  • [ ] docs for kima
  • [ ] docs for pykima
  • [ ] update kima.science
• [ ] ...
• [ ] fix #78
• [ ] fix #75
• [ ] fix #76

[j-faria]

pybind11 extensions are not working in Python 3.11