Fix a bug introduced when we patched the "disallowed global data"

security check.  Not sure why the patch worked for some and not for
others, but this should resolve it either way.  Fixes ticket #1123.

modules/gallery/libraries/MY_Input.php

@@ -26,6 +26,6 @@ class Input extends Input_Core {
    * @return  string
    */
   public function clean_input_keys($str) {
-    return preg_replace('#^[\pL0-9:_.-]++$#uD', '_', $str);
+    return preg_replace('#[^a-zA-Z0-9:_.-]+#', '_', $str);
   }
 }