Bump dependencies

Author: GuilhemN

composer.json

@@ -17,9 +17,9 @@
     ],
     "require": {
         "php": ">=5.3.2",
-        "symfony/framework-bundle": "~2.0|3.*",
-        "symfony/serializer": "~2.0|3.*",
-        "symfony/console": "~2.0|3.*",
+        "symfony/framework-bundle": "~2.3|3.*",
+        "symfony/serializer": "~2.3|3.*",
+        "symfony/console": "~2.3|3.*",
         "willdurand/jsonp-callback-validator": "~1.0"
     },
     "require-dev": {