Release 050

[kkappler]

For some reason, uploading to testpypi is failing with

python -m twine upload --repository testpypi dist/*
Uploading distributions to https://test.pypi.org/legacy/
ERROR    InvalidDistribution: Invalid distribution metadata: unrecognized or malformed field 'license-file'

Not sure why, but getting rid of the archaic setup.py and moving to a pyproject.toml seems like a good place to start.

Update:

• it seems that starting a fresh conda environment got rid of this error and I was able to upload to testpypi