…ann)

This PR was submitted for the master branch but it was merged into the 2.7 branch instead (closes #7243).

Discussion
----------

Removes duplicated Deprecated and adds an example.

Removes the duplicate "Deprecated" after `@deprecated` annotation as was asked in my PR symfony/symfony#20735. Also adds a randomly selected example that shows how the abstract `XXX` should look like and an edge case of `trigger_error()` when deprecating a whole class.

Commits
-------

a2c04e7 Deletes duplicate "Deprecated" and adds a more explicit example.

* 2.7:
  Use PHP 5.5's ::class notation
  [#7243] minor tweak
  Deletes duplicate "Deprecated" and adds a more explicit example.

* 2.8:
  [#7220] some minor tweaks
  Use PHP 5.5's ::class notation
  [#7243] minor tweak
  Deletes duplicate "Deprecated" and adds a more explicit example.
  Accepted Suggestions
  Update 'query_builder' option
  Accepted suggestions in the guard documentation
  Accepted suggestions in the guard documentation
  Accepted suggestions in the guard documentation
  Update guard_authentication.rst
  Use PHP 5.5's ::class notation

* 3.1:
  [#7220] some minor tweaks
  Added "How to Use a Custom Version Strategy for Assets"
  Use PHP 5.5's ::class notation
  [#7243] minor tweak
  Deletes duplicate "Deprecated" and adds a more explicit example.
  Accepted Suggestions
  Update 'query_builder' option
  Accepted suggestions in the guard documentation
  Accepted suggestions in the guard documentation
  Accepted suggestions in the guard documentation
  Update guard_authentication.rst
  Use PHP 5.5's ::class notation

* 3.2: (22 commits)
  add missing config formats
  [#7224] fix indentation
  [#7220] some minor tweaks
  [#7196] add versionadded directive
  Explained how to improve the readability of long numeric literals
  Fix typo in workflow usage code lock
  Added "How to Use a Custom Version Strategy for Assets"
  Use PHP 5.5's ::class notation
  Update state-machines.rst
  [PHPUnitBridge] Fix copy/paste error
  [PHPUnitBridge] Fix copy/paste error
  [#7243] minor tweak
  Deletes duplicate "Deprecated" and adds a more explicit example.
  Accepted Suggestions
  Update 'query_builder' option
  Mentioned %env(...)% variables in Best Practices book
  Accepted suggestions in the guard documentation
  Accepted suggestions in the guard documentation
  Accepted suggestions in the guard documentation
  Update guard_authentication.rst
  ...