Start authentication + improvements for bookmarking tutorial.
Tweak formatting to trigger a rebuild.
Basic edits to bookmarks authentication doc
Fix logout sentence
[fr] bookmarks auth tuto
Remove unnecessary else in example
Improved wording
Improved wording of comment
Remove unnecessary else statements  in examples
[fr] correction
Rename authentication to part two.
corrections after master=>3.0
Merge pull request #1848 from cakephp/bookmarkr-auth

Bookmarkr auth
Fix Collection reference in computed field section
Update component documentation.

Add documentation related to the new initialize() event, and also inline
the API docs into a section. I've also removed the API section as it had
nothing in it once the callbacks were moved.

I've also tried to make the examples clearer by including comments for
different functions context.
fix some typos
[fr] - exception translation
[fr] typos

correct more errors

more typos
Merge pull request #1857 from cakephp/3.0-fr-exceptions

3.0 fr exceptions
Merge pull request #1855 from bcrowe/3.0-computed-field

3.0 - Fix Collection reference in computed field section