Add new setup process based on more modern Python

[luclaurent]

The idea will be to rebuild the Package setup process using

1. More recent modern Python Syntax based on PEP621
2. The use of a Python package management system to be able to build sdistand wheel, run tests, coverage, publish.

For point 1, we can consider the use of setuptools. But point 2 requires a specific tools like Poetry, Hatch, pdm and associated build backend. Hatch seems at this point to be a good basic candidate (see branch new-setup-hatchling).