Make build environment workable

* Add files needed to build documentation. They are copied
  from the cookiecutter repository.

* Replace setup.py and add setup.cfg

* Add tox.ini

* Add requirements.txt and test-requirements.txt

* Fix hacking issue H307 (like imports should be grouped together)

Change-Id: I325bb07233853611e8f0952a554a30dba2b7dfe7
Co-Authored-By: Joshua Harlow <harlowja@yahoo-inc.com>