A basic outline of the structure of the upcoming integration documentation
Create a proper layout file for the integration docs
Bash autocomplete documentation
Google Integration Guide
Mutt Integration Guide
ZSH Integration Guide
Add the integration guide to the documentation index

The layout of the documentation index is possibly starting to strain under the
amount of links I've piled onto it now. I don't think it's completely
overwhelming yet, and for now I'm happy to simply enjoy the fact that ppl is
still simple enough that everything still just about fits on that one flat page.
Merge branch 'integration'