Removed support for zend-stdlib v2 releases

Author: michalbundyra

composer.json

@@ -20,7 +20,7 @@
         "zendframework/zend-http": "^2.5.4",
         "zendframework/zend-math": "^2.7 || ^3.0",
         "zendframework/zend-server": "^2.7",
-        "zendframework/zend-stdlib": "^2.7 || ^3.0",
+        "zendframework/zend-stdlib": "^3.2.1",
         "zendframework/zendxml": "^1.0.2"
     },
     "require-dev": {