replace Exception on GeneralException (Config.php)

Config.php

@@ -33,7 +33,7 @@ class ConfigArray extends ArrayObject
     public function offsetGet($index) 
     {
         if (!$this->offsetExists($index)) {
-            throw new Exception('Configuration variable "' . $index . '" undefined');
+            throw new GeneralException('Configuration variable "' . $index . '" undefined');
         }
         return parent::offsetGet($index);
     }