set entries update isdraft to string value false

to be able to publish draft entries from dashboard

References #160

include/functions_entries.inc.php

@@ -1402,6 +1402,8 @@ function serendipity_updertEntry($entry) {
             }
         }
 
+        if (!$entry['isdraft'] || $entry['isdraft'] == 0) $entry['isdraft'] = 'false';
+
         //if (!serendipity_db_bool($entry['isdraft']) && !serendipity_db_bool($_entry['isdraft'])) {
             $entry['last_modified'] = time();
         //}