Merge branch '3.2' into 3.3

* 3.2: (39 commits)
  updating instance
  Avoid backticks in shell scripts
  Update optional_dependencies.rst
  Fix xml blocks
  pass only strings to loadUserByUsername()
  Fix Authenticator Class (getCredentials) example
  Documented addAnnotatedClassesToCompile() and the use of class patterns
  Added the picture that shows how GuardAuthenticationListener calls Authentication Guard methods.
  [symfony#7205] minor tweak
  Simplified the use of transChoice()
  [symfony#7875] minor tweaks
  Minor fix
  Minor changes
  Properly show all events and describe guard events
  [symfony#7891] remove not needed sentence
  [symfony#7773] fix line length
  Add helpful remarks on custom DataCollector
  Remove use of deprecated security.exception_listener.class parameter
  Update resources.rst
  Fix incoherent ut8mb4 collation in Doctrine setup
  ...

Author: weaverryan

_images/security/authentication-guard-methods.png

@@ -348,9 +348,17 @@ The end user can provide values in any configuration file:
     .. code-block:: xml
 
         <!-- app/config/config.xml -->
-        <parameters>
-            <parameter key="acme_blog.author.email">fabien@example.com</parameter>
-        </parameters>
+        <?xml version="1.0" encoding="UTF-8" ?>
+        <container xmlns="http://symfony.com/schema/dic/services"
+            xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+            xsi:schemaLocation="http://symfony.com/schema/dic/services
+                http://symfony.com/schema/dic/services/services-1.0.xsd">
+
+            <parameters>
+                <parameter key="acme_blog.author.email">fabien@example.com</parameter>
+            </parameters>
+
+        </container>
 
     .. code-block:: php