upd for sf 4

Author: andreybolonin

composer.json

@@ -46,7 +46,7 @@
         "doctrine/mongodb-odm": ">=1.0.2",
         "doctrine/orm": ">=2.5.0",
         "doctrine/common": ">=2.5.0",
-        "symfony/yaml": "~2.6|~3.0",
+        "symfony/yaml": "~2.6|~3.0|~4.0",
         "phpunit/phpunit": "*"
     },
     "suggest": {