Make the bookmarks tutorial the recommended one.

I think this is a more successful and useful tutorial. Using it as the
primary one will hopefully give new developers a better experience.
Change bookmarkr -> bookmarker
Update fr quickstart with bookmarker
Update fr index Blog -> Bookmarker
Merge pull request #1954 from cakephp/bookmark-primary

Make the bookmarks tutorial the recommended one.
Fix closure spacing in code examples
Merge pull request #1959 from bcrowe/3.0-closure-spacing

3.0 - Fix closure spacing in code examples
Add info about new Auth events.

Refs cakephp/cakephp#5097
Update events.rst

EventListener is deprecated, use EventListenerInterface instead.
Merge pull request #1963 from vttn/patch-2

EventListener is deprecated, use EventListenerInterface instead.
Fix typo in method name.
Document direct task execution subcommand necessity

In order to be able to execute a task via its parent shell, a sub command must be added to the Shell's option parser.
Merge pull request #1966 from robertscherer/patch-1

Document direct task execution subcommand necessity
Fix wrong method name

isWithinPast should be wasWithinLast
Merge pull request #1968 from berrygoudswaard/patch-1

Fix wrong method name
Merge pull request #1962 from cakephp/3.0-auth-events

Add info about new Auth events.
update database configuration

change 'login' tuo 'username'
Merge pull request #1969 from cewi/patch-1

update database configuration example
update to follow en changes

- #1962
- #1963
- #1966
- #1968
fix typos form comments