add db in zip backup

root/cigala.php

@@ -641,6 +641,7 @@ elseif (isset($_GET['zip'])) {
         $messages[] = 'An error occurred while adding “'.$n.'” to the zip archive.';
       }
     }
+    $zip->addFile($settings['db'], 'cigala.db');
     $zip->close();
     if (count($messages) > 0) {
       inform($messages, 'actions');