* Add `setuptools_scm` for dynamic zero-config Python versioning
This removes the need for manually bumping versions in the Python
bindings.
For the wheel uploads, the correct semver version is inferred in the case
of tagged commits, which is exactly the case in GitHub CI.
The docs were updated to reflect the changes in the release workflow.
* Add separate version variable and module, use PEP484-compliant exports
This is the best practice mentioned in the `setuptools_scm` docs, see
https://setuptools-scm.readthedocs.io/en/latest/usage/#version-at-runtime.
This commit adds a small section on how to install and build Python
bindings wheels to the docs, as well as a link to it from the main readme.
Notes were added that clearly state availability of Python wheels based
on Python version and OS/architecture combinations.
For the guide to build a wheel from source, the best practice of
creating a virtual environment and activating it before build was
detailed. Also, a note on the required installation of Bazel was added,
with a link to the official docs on installation.
