Jni

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- Add support for Python 3.13
- Drop support for Python 3.8
- jni.c and pvm.c (useful for embedded python applications) have been added.
- Unittest have been performed for much more JVMs.
- Setup fixes.
- Setup (dependencies) update.

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- Tox configuration has been moved to pyproject.toml
- Setup update (now based on tox >= 4.0).
- Add support for Python 3.10, 3.11 and 3.12
- Drop support for Python 3.7
- Add support for PyPy 3.9 and 3.10
- Copyright year update.

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- Drop support for Python 3.6
- Setup update.

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- dll_path argument of load() can also be type os.PathLike.
- Copyright year update.
- Setup update.

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- Add support for Python 3.9
- General update, improvements and cleanup.
- Setup update and improvements.
- Fixed docs setup.

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- Drop support for Python2
- Update of license info.
- Setup update.