Merge branch '2.4' into 2.5

* 2.4:
  updated VERSION for 2.4.7
  updated CHANGELOG for 2.4.7
  bumped Symfony version to 2.3.18
  updated VERSION for 2.3.17
  update CONTRIBUTORS for 2.3.17
  updated CHANGELOG for 2.3.17
  added XSD to PHPUnit configuration
  add missing docblock for ProcessBuilder::addEnvironmentVariables()
  bug #11319 [HttpKernel] Ensure the storage exists before purging it in ProfilerTest
  [Translation] Added unescaping of ids in PoFileLoader
  updated italian translation for validation messages
  [DomCrawler] Fix docblocks and formatting.
  [DomCrawler] Remove the query string and the anchor of the uri of a link
  Simplified the Travis test command
  Remove Expression Language services when the component is unavailable
  [Console] Make sure formatter is the same

Conflicts:
	src/Symfony/Component/HttpKernel/Kernel.php

phpunit.xml.dist

@@ -1,14 +1,15 @@
 <?xml version="1.0" encoding="UTF-8"?>
 
-<phpunit backupGlobals="false"
+<phpunit xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:noNamespaceSchemaLocation="http://schema.phpunit.de/4.1/phpunit.xsd"
+         backupGlobals="false"
          backupStaticAttributes="false"
          colors="true"
          convertErrorsToExceptions="true"
          convertNoticesToExceptions="true"
          convertWarningsToExceptions="true"
          processIsolation="false"
          stopOnFailure="false"
-         syntaxCheck="false"
          bootstrap="vendor/autoload.php"
 >
     <testsuites>