[drupal-docs] Handbook Root books

[vlado]

> Why does there need to be a place for end end users in the Drupal
> handbook?  They won't look there, they'll go to their own site admin.
It's a good practise to refer to the vendor docs from your website, as
extra help. Call me a lazy site admin :) But a central 'generic' enduser
documentation is a good thing. It helps people deploy websites quicker,
as they can both borrow or refer to the master docs.

Vlado