[WIP] Initial version of creating a basic CMS

This is a complete tutorial on creating a simple (or basic) CMS
using the RoutingAuto bundle.

See https://github.com/dantleech/tutorial-basic-cms

This was originally concieved as a blog post, maybe it should
stay that way...
Added some images and split into 3 sections

- Added some diagrams
- Various
Added PHP shortcuts
More explanation, diagram and CR fixes
Homepage section
Updated again.