Quick fix for data container merging

Author: stevewest

src/DataContainer.php

@@ -228,7 +228,7 @@ public function merge($arg)
 		}, func_get_args());
 
 		array_unshift($arguments, $this->data);
-		$this->data = call_user_func_array('Arr::merge', $arguments);
+		$this->data = call_user_func_array('\Fuel\Common\Arr::merge', $arguments);
 
 		$this->isModified = true;