[School-of-data] Move http://handbook.schoolofdata.org to http://schoolofdata.org/handbook

[Rufus Pollock]

Hi all,

Wanted to propose the idea of moving the handbook from subdomain to
suburl. We'd still use sphinx but we'd use Wordpress API to push built
sphinx docs up into wordpress.

Benefits:

* Integrated experience
* Shared theming
* Nicer urls!

Costs:

* Some coding effort
* Ongoing maintenance (site won't automatically rebuild as it does via
readthedocs)

Rufus