PEP621: Migrate setup.py config into pyproject.toml

[cclauss]

Proposed changes

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PEP621 encourages the Python community to migrate away from complex setup.cfg + setup.py files by putting config data in pyproject.toml.

Migrate setup.py to setup.cfg using setuptools-py2cfg plus manual modifications.
Then migrate setup.cfg to pyproject.toml using ini2toml to do the file conversion and running validate-pyproject in pre-commit to validate the results.

• https://setuptools.pypa.io/en/latest/userguide/pyproject_config.html
• https://packaging.python.org/en/latest/tutorials/packaging-projects/#creating-pyproject-toml

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[codecov]

Codecov Report

Merging #421 (1750a5c) into master (b14808e) will increase coverage by 0.20%.
The diff coverage is n/a.

❗ Current head 1750a5c differs from pull request most recent head bb91933. Consider uploading reports for the commit bb91933 to get more accurate results

@@            Coverage Diff             @@
##           master     #421      +/-   ##
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+ Coverage   93.59%   93.80%   +0.20%     
==========================================
  Files          34       34              
  Lines        1078     1113      +35     
  Branches       63      130      +67     
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+ Hits         1009     1044      +35     
  Misses         44       44              
  Partials       25       25              

Flag	Coverage Δ
unittests	93.80% <ø> (+0.20%)	⬆️

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see 9 files with indirect coverage changes

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[nijel]

Can we remove the requirements.txt? If you think it's too big change to do in this PR, please create another PR on top of this so that we can see a full scope of changes this will bring. Thanks.

[atodorov]

IMO first remove dependencies from setup.py as a separate PR and then come back to this.

Update: this is already inside the removed requirements.txt.

[cclauss]

% git rm requirements.txt

Test failures related to #427 and #428

[atodorov]

Already updated in #434 so I think you can drop this change.

[atodorov]

Why remove requirements.txt ?

[cclauss]

Perhaps read the commit message.