Merge branch '2.3' into 2.5

* 2.3:
  [Doc] Use Markdown syntax highlighting
  [Finder] tweaked docs
  [Finder] Add info about possibilities offered by SplFileInfo
  fix components tests
  [Intl] FIxed failing test
  [Intl] Generated the data for ICU version 54-rc
  [EventDispatcher] fix doc bloc on EventDispatcherInterface
  [Validator] Update validators.zh_CN.xlf, fix translation error
  bumped Symfony version to 2.3.21
  updated VERSION for 2.3.20
  update CONTRIBUTORS for 2.3.20
  updated CHANGELOG for 2.3.20
  [Intl] Integrated ICU data into Intl component

Conflicts:
	src/Symfony/Component/HttpKernel/Kernel.php
	src/Symfony/Component/Intl/ResourceBundle/LocaleBundle.php

README.md

@@ -9,51 +9,63 @@ standard or the PEAR naming convention.
 
 First, register the autoloader:
 
-    require_once __DIR__.'/src/Symfony/Component/ClassLoader/UniversalClassLoader.php';
+```php
+require_once __DIR__.'/src/Symfony/Component/ClassLoader/UniversalClassLoader.php';
 
-    use Symfony\Component\ClassLoader\UniversalClassLoader;
+use Symfony\Component\ClassLoader\UniversalClassLoader;
 
-    $loader = new UniversalClassLoader();
-    $loader->register();
+$loader = new UniversalClassLoader();
+$loader->register();
+```
 
 Then, register some namespaces with the `registerNamespace()` method:
 
-    $loader->registerNamespace('Symfony', __DIR__.'/src');
-    $loader->registerNamespace('Monolog', __DIR__.'/vendor/monolog/src');
+```php
+$loader->registerNamespace('Symfony', __DIR__.'/src');
+$loader->registerNamespace('Monolog', __DIR__.'/vendor/monolog/src');
+```
 
 The `registerNamespace()` method takes a namespace prefix and a path where to
 look for the classes as arguments.
 
 You can also register a sub-namespaces:
 
-    $loader->registerNamespace('Doctrine\\Common', __DIR__.'/vendor/doctrine-common/lib');
+```php
+$loader->registerNamespace('Doctrine\\Common', __DIR__.'/vendor/doctrine-common/lib');
+```
 
 The order of registration is significant and the first registered namespace
 takes precedence over later registered one.
 
 You can also register more than one path for a given namespace:
 
-    $loader->registerNamespace('Symfony', array(__DIR__.'/src', __DIR__.'/symfony/src'));
+```php
+$loader->registerNamespace('Symfony', array(__DIR__.'/src', __DIR__.'/symfony/src'));
+```
 
 Alternatively, you can use the `registerNamespaces()` method to register more
 than one namespace at once:
 
-    $loader->registerNamespaces(array(
-        'Symfony'          => array(__DIR__.'/src', __DIR__.'/symfony/src'),
-        'Doctrine\\Common' => __DIR__.'/vendor/doctrine-common/lib',
-        'Doctrine'         => __DIR__.'/vendor/doctrine/lib',
-        'Monolog'          => __DIR__.'/vendor/monolog/src',
-    ));
+```php
+$loader->registerNamespaces(array(
+    'Symfony'          => array(__DIR__.'/src', __DIR__.'/symfony/src'),
+    'Doctrine\\Common' => __DIR__.'/vendor/doctrine-common/lib',
+    'Doctrine'         => __DIR__.'/vendor/doctrine/lib',
+    'Monolog'          => __DIR__.'/vendor/monolog/src',
+));
+```
 
 For better performance, you can use the APC based version of the universal
 class loader:
 
-    require_once __DIR__.'/src/Symfony/Component/ClassLoader/UniversalClassLoader.php';
-    require_once __DIR__.'/src/Symfony/Component/ClassLoader/ApcUniversalClassLoader.php';
+```php
+require_once __DIR__.'/src/Symfony/Component/ClassLoader/UniversalClassLoader.php';
+require_once __DIR__.'/src/Symfony/Component/ClassLoader/ApcUniversalClassLoader.php';
 
-    use Symfony\Component\ClassLoader\ApcUniversalClassLoader;
+use Symfony\Component\ClassLoader\ApcUniversalClassLoader;
 
-    $loader = new ApcUniversalClassLoader('apc.prefix.');
+$loader = new ApcUniversalClassLoader('apc.prefix.');
+```
 
 Furthermore, the component provides tools to aggregate classes into a single
 file, which is especially useful to improve performance on servers that do not