* Fixing the package to include commands.

Fixes #1645

For details on this feature, see:
https://setuptools.readthedocs.io/en/latest/setuptools.html#configuring-setup-using-setup-cfg-files

Setuptools allows using setup.cfg as a configuration file to define the
package metadata and options. This approach reduces boilerplate code in
favor of a declarative configuration. Down the road, this approach also
allows for automation through scripts and tools.

Python 3.4 has been EOL since 2019-03-18.

Removing from the test matrix helps reduce testing resources.

For additional details on unsupported Python versions, see:

https://devguide.python.org/devcycle/#end-of-life-branches

tox can now always be used as the test entry point and allows for
contributors to easily test the full test matrix locally.

Starting with setuptools v41.5.0 (27 Oct 2019) the `setup.py test`
command is formally deprecated. It now emits a warning on use. Prior to
this version, it use was discouraged by the setuptools developers.

Now, always use tox as the one testing entry point. It handles multiple
version of Python and Redis.

The Travis CI configuration was reworked to use tox to install
dependencies and run tests in the same manner that contributors would do
locally.

Modern Python environments have setuptools or pip installed. The
distutils fallback is unnecessary.