Update Documentation from Py2 to Py3

[JamesPHoughton]

Continuing the thread from #53 (comment)

Hi @osychenko,
Moving the thread to a new issue - updating documentation deserves it's own discussion!

It would be super fantastic to have your help with the docs. Right now, I use sphinxdoc to format restructured text into the format you see on readthedocs. Edits are made to .rst files in the docs directory of the repository. Then you can build them on your local machine using the sphinx package, and view the HTML in the _build directory. Took me a few tries to work that out, but the sphinx package documentation is pretty good. (It had better be...) The basic syntax is to, once changes are made:

cd docs\
make clean
make html

If you fork the PySD repository and make changes, then when you PR and I merge everything back into the master branch, readthedocs will load from the PySD master repo and rebuild and serve them.

[sepiatone]

Hi James,

I made some changes to the documentation - minor stuff while I understand how sphinx and restructured text work. I've created a pull request for you perusal.

Aditya