Set up GitHub Actions

[elbeejay]

Set up some GitHub actions starting with a simple continuous integration workflow to try installing the GOSTnets package on the 3 major operating systems (Linux, Windows, MacOS) for Python 3.8 and then running Python -c import GOSTnets as a very basic test of the package having installed and existing.

Right now we are limited to Python 3.8 because of the hard-pinned dependency rtree-0.9.3 per the project's readme.

[g4brielvs]

@elbeejay Thank you for opening this PR. While this testing workflow can go in parallel, I'd recommend migrating to pyproject.toml first (#40 and #41), including the dependencies and optional dependencies. For example, in the new setup, the dependencies can be added and pinned and the installation could be simplified to pip install gostnets or pip install "gostnets[optimization]" (or even include all dependencies by default because they are not large). Then this PR can be updated and merged. What are your thoughts?

Additionally, the documentation, tests and release workflow (e.g., BlackMarblePy) can also be prioritized. If you agree with the course of action, could you please create and prioritize these as tasks?

[elbeejay]

@elbeejay Thank you for opening this PR. While this testing workflow can go in parallel, I'd recommend migrating to pyproject.toml first (#40 and #41), including the dependencies and optional dependencies. For example, in the new setup, the dependencies can be added and pinned and the installation could be simplified to pip install gostnets or pip install "gostnets[optimization]" (or even include all dependencies by default because they are not large). Then this PR can be updated and merged. What are your thoughts?

Sure, I'd just started here because the PEP stuff wasn't clear to me (from here) but now that we've cleared that up I can set up the pyproject.toml.

[g4brielvs]

@elbeejay #40 is now closed.

[elbeejay]

Added a "publish" workflow for automatic publishing to pypi. May requre configuration on the pypi side per this document

[g4brielvs]

Added a "publish" workflow for automatic publishing to pypi. May requre configuration on the pypi side per this document

@elbeejay Thanks! Merging (we can open other PRs to complement this basic setip). FYI I have requested a worldbank organization on PyPI, but I'll add it manually in the meantime in the next release.