minor #5587 [2.6] Don't use deprecated features (WouterJ)

This PR was submitted for the 2.6 branch but it was merged into the 2.7 branch instead (closes #5587).

Discussion
----------

[2.6] Don't use deprecated features

| Q | A
| --- | ---
| Doc fix? | yes
| New docs? | no
| Applies to | 2.6+
| Fixed tickets | -

Commits
-------

b30e432 [2.6] Don't use deprecated features

Author: xabbuh

book/templating.rst

@@ -1191,7 +1191,7 @@ is a :class:`Symfony\\Bundle\\FrameworkBundle\\Templating\\GlobalVariables`
 instance which will give you access to some application specific variables
 automatically:
 
-``app.security``
+``app.security`` (deprecated as of 2.6)
     The security context.
 ``app.user``
     The current user object.

cookbook/form/dynamic_form_modification.rst

@@ -395,7 +395,7 @@ it with :ref:`dic-tags-form-type`.
         <!-- app/config/config.xml -->
         <services>
             <service id="app.form.friend_message" class="AppBundle\Form\Type\FriendMessageFormType">
-                <argument type="service" id="security.context" />
+                <argument type="service" id="security.token_storage" />
                 <tag name="form.type" alias="friend_message" />
             </service>
         </services>

cookbook/logging/channels_handlers.rst

@@ -15,7 +15,7 @@ the channel).
 .. note::
 
     Each channel corresponds to a logger service (``monolog.logger.XXX``)
-    in the container (use the ``container:debug`` command to see a full list)
+    in the container (use the ``debug:container`` command to see a full list)
     and those are injected into different services.
 
 .. _logging-channel-handler: