Bug fix to be able to ignore auto returning pk for inserts

Some tables do not have primary keys, so an override code is needed to
avoid getting auto returning set there.
If db exec is called 'NULL' (or the async version), then no RETURNING is
added or checked.

www/admin/edit_base.inc

@@ -253,7 +253,7 @@
 					for ($i = 0; $i < count($output); $i ++)
 					{
 						$t_q = "('".$form->db_escape_string($output[$i])."')";
-						$form->db_exec($q.$t_q);
+						$form->db_exec($q.$t_q, 'NULL');
 					}
 					$elements[] = $form->form_create_element("filename");
 				}

www/admin/edit_order.php

@@ -29,7 +29,6 @@
 	// set session name
 	define('SET_SESSION_NAME', EDIT_SESSION_NAME);
 	require(LIBS."Class.Login.inc");
-	require(LIBS."Class.DB.IO.inc");
 	require(LIBS.'Class.Smarty.Extend.inc');
 
 	// default lang