relativity_views.inc : field sort by parent title

The absence of one line in relativity_views.inc prevents the option to sort table or list views by the Relativity: Parent Title field.
After inserting the + 'sortable' => true, line (and refreshing the views cache by resubmitting the modules admin page), I have experienced no problems (so far ...)

Apologies for not being able to write proper patch files, so here's my approximation:

<?php

    'fields' => array(
      'title' => array(
        'name' => t('Relativity: Parent Title'),
        'handler' => array(
          'views_handler_field_relativity_parent_title'    => t('As Link'),
          'views_handler_field_relativity_parent_title_nl' => t('Without Link'),
        ),
+       'sortable' => true,
        'addlfields' => array('nid'),
        'help' => t('Display the title of the parent node'),
      ),
    ),
    'sorts' => array(

?>

Hope it helps.