Make sure symfony uses namespaced classes

Author: greg0ire

composer.json

@@ -24,7 +24,7 @@
         "symfony/debug": "^2.8 || ^3.3 || ^4.0",
         "symfony/dependency-injection": "^2.8 || ^3.3 || ^4.0",
         "symfony/doctrine-bridge": "^2.8 || ^3.3 || ^4.0",
-        "symfony/framework-bundle": "^2.8 || ^3.3 || ^4.0",
+        "symfony/framework-bundle": "^2.8.18 || ^3.3 || ^4.0",
         "symfony/http-foundation": "^2.8 || ^3.3 || ^4.0",
         "symfony/http-kernel": "^2.8 || ^3.3 || ^4.0",
         "symfony/monolog-bundle": "~3.1",