Fix issue where orderBy strips spaces from fieldname

MysqliDb.php

@@ -1093,7 +1093,7 @@ class MysqliDb
     {
         $allowedDirection = Array("ASC", "DESC");
         $orderbyDirection = strtoupper(trim($orderbyDirection));
-        $orderByField = preg_replace("/[^-a-z0-9\.\(\),_`\*\'\"]+/i", '', $orderByField);
+        $orderByField = preg_replace("/[^ -a-z0-9\.\(\),_`\*\'\"]+/i", '', $orderByField);
 
         // Add table prefix to orderByField if needed.
         //FIXME: We are adding prefix only if table is enclosed into `` to distinguish aliases