- leave sphinx and sphinx_rtd_theme in the extra and move the rest
to docs/requirements.txt, which is used by RTD
- docutils-0.18 caused a build failure
* Added: Sphinx configuration including readthedocs config
* Added: Sphinx fabric task to auto-document the project
* Fixed: Some issues in the code causing autodoc to fail when parsing
* Added: Manual docs - structure, proof of concepts and RsT examples
* Fixed: RsT formatting in docstrings
* Fixed: Some adjacent minor style and lint issues