Correct some grammatical issues with the new topguests feed.

webtools/partytool/views/feeds/topguests.thtml

@@ -8,7 +8,7 @@
     <?php foreach($items as $item):?>
     <item>
       <title><?php echo $item['parties']['name'].' ('.$item[0]['count'].')'; ?></title>
-      <description><?php echo $item['parties']['name'].' - '.$item[0]['count'].' guests.'; ?></description>
+      <description><?php echo $item['parties']['name'].' - '.$item[0]['count'].' guest'.(($item[0]['count'] != 1) ? 's' : ''); ?></description>
       <link><?php echo APP_BASE.$html->url('/parties/view/'.$item['guests']['id']); ?></link>
     </item>
     <?php endforeach; ?>