Merge branch '2.3' into 2.6

* 2.3:
  [Routing][DependencyInjection] Support .yaml extension in YAML loaders
  [DX] improve file loader error for router/other resources in bundle
  [FrameworkBundle] Fix Routing\DelegatingLoader resiliency to fatal errors
  [HttpKernel] Cleanup ExceptionListener
  CS fixes
  [DependencyInjection] Show better error when the Yaml component is not installed
  [2.3] SCA for Components - reference mismatches
  [2.3] Static Code Analysis for Components
  [Translation][fixed test] refresh cache when resources are no longer fresh.
  [Validator] Added missing Simplified Chinese (zh_CN) translations
  [FrameworkBundle] Workaround php -S ignoring auto_prepend_file

Conflicts:
	src/Symfony/Bundle/FrameworkBundle/Tests/Translation/TranslatorTest.php
	src/Symfony/Component/Config/Exception/FileLoaderLoadException.php
	src/Symfony/Component/Console/Descriptor/TextDescriptor.php
	src/Symfony/Component/Console/Helper/TableHelper.php
	src/Symfony/Component/Console/Tests/Formatter/OutputFormatterTest.php
	src/Symfony/Component/DependencyInjection/Dumper/PhpDumper.php
	src/Symfony/Component/DependencyInjection/Dumper/YamlDumper.php
	src/Symfony/Component/HttpKernel/Debug/TraceableEventDispatcher.php
	src/Symfony/Component/HttpKernel/Tests/Debug/TraceableEventDispatcherTest.php
	src/Symfony/Component/PropertyAccess/PropertyAccessor.php
	src/Symfony/Component/Yaml/Tests/InlineTest.php

Author: nicolas-grekas

Http/Firewall/DigestAuthenticationListener.php

@@ -161,7 +161,7 @@ public function getResponse()
 
     public function getUsername()
     {
-        return strtr($this->elements['username'], array("\\\"" => "\"", "\\\\" => "\\"));
+        return strtr($this->elements['username'], array('\\"' => '"', '\\\\' => '\\'));
     }
 
     public function validateAndDecode($entryPointKey, $expectedRealm)