Basic doc updates

[Rukkh]

Tidied up the issue identified with the links to python modules.

Tweaked a few other things to make Sphinx happy (probably could have ignored warnings but was a good exercise in learning reST, Sphinx etc. (Also git)

Happy to do some bigger doc updates, but don't want to dive in too deep if you have other plans for the documentation.

Blake

[m-mcgowan]

Many thanks for this @Rukkh! All looks good. Can you tell me about the change of the theme from "deafult" to "classic"?

[Rukkh]

http://sphinx-doc.org/theming.html

The theme the brewpi user docs are using are the original 'default' theme based off the python documentation look. At some point it looks like Sphinx has changed the 'default' theme to the alabaster one based off the ReadTheDocs.com theme and they've renamed 'default' to 'classic'.
When you leave 'default' in there sphinx gives you a warning that the 'default' has changed. I think that it still gives you the same theme output but i guess there's a risk in the future they make the 'default' named theme the other one.

I'm just a little bit conditioned to react to unnecessary compiler output warnings.