Rename file to have more-relevant filename.
Move all kinds of things around.

* Collapse core-libraries and core-utility libraries. Not even I can
  remember what goes where. One flatter directory will be much saner to
  handle.
* Remove TOC stubs. These were pointless fluff that just make the docs
  more bloated while contributing nothing.
* Expose more information in the top level TOC. Instead of forcing
  people to hunt, try and bubble up some sections many people might be
  interested in.
Make TOC use MVC ordering.
Remove duplicate TOC entries.
[fr] folow on french translation
Reorder controller, model, view.

Also sync up the epub and pdf contents.
Sync up fr contents.
Merge pull request #1805 from cakephp/flatter-toc

Flatter TOC
Cleaning up code in REST section examples
[fr] folow 888e4a88