refs #12
refs #11, simplify versioning, document install example, env_vars used as lists but received as str
refs #13: for github pages, do not render with jekyll
* get the path right on conf.py
* make Sphinx doc parts easier to synchronize
* merge docs/index.rst into docs/source/index.rst
* new install doc
* pull the project landing page into the Sphinx docs (might discard this since it is ugly here)