Move from setup.py to pyproject.toml

[fralau]

There is a need to move the project to pyproject.toml.

We will use a new update_pypi.sh to update pypi. The general idea is that github keeps the cutting edge release, and a release to pypi is a deliberate (not automatic) decision.

The version number is in the pyproject.toml and it is the reference for the rest of the project..

[fralau]

Solved in 1.3.6