Move docs to Sphinx 1.3b2

[patricksnape]

Now we are using Napolean, which has been introduced to
Sphinx 1.3, and parses both google doc style comments and
numpydoc style comments. Most importantly, it supports things
like Yield which is very nice. Unfortunately, it parses cross
references as code blocks and so I had to add some hacky code
that basically overrides the formatting of the cross references
in CSS.

I also bumped the requirements file.

[jabooth]

+1