CAS-14475

[amcnicho]

Fix casaconfig pip install warning due to missing pyproject.toml.

When pip installing casaconfig this deprecation warning is seen:

DEPRECATION: casaconfig is being installed using the legacy 'setup.py install' method, because it does not have a 'pyproject.toml' and the 'wheel' package is not installed. pip 23.1 will enforce this behaviour change. A possible replacement is to enable the '--use-pep517' option.

This branch replaces setup.py with pyproject.toml.

• working build
• CI changes
• README/docs

[amcnicho]

@jmarvil has indicated that this can merge. IIUC one last commit (to change the tag back to what it should be on the main branch) is all that should be needed.

[bgarwood]

@vsuorant I'll take care of this, but I want to make sure I get the sequence right before I do this. Do I approve the PR first and then edit the resulting README.md in master to get the appropriate next release (1.0.2) and then create the release here in the usual way or should the README.md be edited in this branch first, before the PR is approved?