Pytest-harvest

- Fixed issue with doctests. PR [41](https://github.com/smarie/python-pytest-harvest/pull/41) by [larsoner](https://github.com/larsoner)

See [documentation page](https://smarie.github.io/python-pytest-harvest/changelog/) for details.

- Fixed issue sometimes happening when xdist is not installed. Fixed [40](https://github.com/smarie/python-pytest-harvest/issues/40)

See [documentation page](https://smarie.github.io/python-pytest-harvest/changelog/) for details.

- packaging improvements: set the "universal wheel" flag to 1, and cleaned up the `setup.py`. In particular removed dependency to `six` for setup and added `py.typed` file, as well as set the `zip_safe` flag to False. Removed tests folder from package. Fixes [38](https://github.com/smarie/python-pytest-harvest/issues/38)

See [documentation page](https://smarie.github.io/python-pytest-harvest/changelog/) for details.

When `pytest-xdist` is used to distribute tests, worker node results are automatically stored in a file at the end of their respective pytest session using pickle, in a temporary `.xdist_harvested/` folder. These results are automatically retrived and consolidated when any of the `get_[module/session]_results_[dct/df]` method is called from the master node. Finally, the temporary folder is deleted at the end of master node session. Fixes [36](https://github.com/smarie/python-pytest-harvest/issues/36)

New function `get_fixture_store(session)` to replace `FIXTURE_STORE`. It is robust to xdist distribution, hence preferred over direct use of `FIXTURE_STORE`.

See [documentation page](https://smarie.github.io/python-pytest-harvest/changelog/) for details.

- For each of the `[module/session]_results_[dct/df]` fixtures, an equivalent `get_<fixture_name>(session, ...)` helper function is available. This allows users to access the same level of functionality than the fixture, in places where fixtures are not available (typically in a pytest hook such as the `pytest_sessionfinish` session finish hook). In addition the default `FIXTURE_STORE` is now a package variable, available directly or through the session-scoped `fixture_store` fixture. Fixed [33](https://github.com/smarie/python-pytest-harvest/issues/33) and [#34](https://github.com/smarie/python-pytest-harvest/issues/34).

- Added an example in the documentation on how to use with pytest-xdist. Fixes [32](https://github.com/smarie/python-pytest-harvest/issues/32)

See [documentation page](https://smarie.github.io/python-pytest-harvest/changelog/) for details.

Added a `pyproject.toml` file.

See [documentation page](https://smarie.github.io/python-pytest-harvest/changelog/) for details.