Pathlib3x

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2023-07-13:
- require minimum python 3.8
- remove python 3.7 tests
- introduce PEP517 packaging standard
- introduce pyproject.toml build-system
- remove mypy.ini
- remove pytest.ini
- remove setup.cfg
- remove setup.py
- remove .bettercodehub.yml
- remove .travis.yml
- update black config
- clean ./tests/test_cli.py
- add codeql badge
- move 3rd_party_stubs outside the src directory to ``./.3rd_party_stubs``
- add pypy 3.10 tests
- add python 3.12-dev tests

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2022-06-03: use io.encoding only on 3.10 upwards

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2022-06-03: define __fspath__ only on python >= 3.10

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2022-06-03: use io.encoding only on 3.10 upwards

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2022-06-03:
- upgrade to pathlib python 3.11a0 version
- upgrade to github actions v3

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2020-10-09: service release
- update travis build matrix for linux 3.9-dev
- update travis build matrix (paths) for windows 3.9 / 3.10