Modernized the packaging / testing configuration

[agronholm]

• Moved metadata to setup.cfg, keeping just a stub setup.py file for editable installs (needed for the time being)
• Switched from Travis to Github Actions
• Switched from unittest to pytest
• Added tox configuration for easy local testing across different Python versions

[agronholm]

I don't know why the workflow was not triggered.

[pganssle]

I don't know why the workflow was not triggered.

I suspect that you cannot add new workflows that are triggered unless you have write access to the repository? I don't know the exact rules, but it's common to restrict this sort of thing so that people don't open thousands of PRs that run bitcoin miners or whatever on random unmaintained OSS projects.

[agronholm]

@regebro do you want to move tzlocal to use the src layout? I can modify this PR accordingly.

[regebro]

No, I prefer this layout, unless there is some new reason against it.

[agronholm]

The reason is that running the tests in the project directory will import the project source rather than the installed version of the package. That in turn means that the test suite won't expose any mishaps in the packaging (like missing files in MANIFEST.in). Moving the source to src/ prevents that from happening. I've switched to the src layout in all my recent projects and am in the process of migrating older projects to that as well as I update them.

[agronholm]

Looks like the workflow is running now, and failing on Windows.

[regebro]

Yeah, I wonder what the windows time zone is in github actions.

[agronholm]

Well, the traceback says Etc/GMT. Go figure.

[agronholm]

Oh, could this be caused by the missing tzdata?

[agronholm]

I added tzdata in #100, but that is now failing with a different error: https://github.com/regebro/tzlocal/pull/100/checks?check_run_id=1176719892

[agronholm]

Oh, it looks like a unix specific test. It should probably be skipped on Windows, yes?