Add ci and release github actions for easier maintenance

[mbachry]

Linux and Mac binary wheels were handled by travis builds, but it seems that travis is currently broken. Instead of fixing it, I suggest a single github action that builds wheels for all three platforms (thus replacing both travis and appveyor). The action is triggered by pushing a git tag with v prefix (eg. v2.1.0) - this should be the only operation required to make a full release.

Some changes:

• build.yml action that builds and uploads a release on a new git tag; regular pushes upload to test.pypi.org (matches current behavior)
• added setuptools_scm, so you don't have to edit version.py (the version is picked automatically from the current git tag)
• a simple ci.yml for running tests

Here's my test release: https://test.pypi.org/project/hiredis-mytest/0.0.0.dev0/#files (all currently supported platforms are there)

Note that TEST_PYPI_API_TOKEN and PYPI_API_TOKEN pypi secrets would have to be created in github repo settings for pypi uploads to work.

[jlvrhee]

Is there anyone who can merge this pull request, so we get an updated wheel in pypi?

Thanks in advance

[ifduyue]

Also Github Actions didn't trigger.

I think those .github files should go first into master branch and then github actions can be triggered.
But I can't add PyPI tokens to this repo's github action secrets. This needs some help from someone with repo admin rights.

[rth]

Yes, makes sense. Looks like it's blocked by https://github.com/redis/hiredis-py/issues/63 for now.