Time markup for Last Changed field

This adds semantic markup to the "last change" date in the article footer. This change should not have any impact on the rendering of the page.

Author: saschaleib

inc/template.php

@@ -948,15 +948,16 @@ function tpl_pageinfo($ret = false)
         }
     }
     $fn = utf8_decodeFN($fn);
-    $date = dformat($INFO['lastmod']);
+    $dateLocal = dformat($INFO['lastmod']);
+    $dateIso = date(DATE_ISO8601, $INFO['lastmod']);
 
     // print it
     if ($INFO['exists']) {
         $out = '<bdi>' . $fn . '</bdi>';
         $out .= ' · ';
         $out .= $lang['lastmod'];
         $out .= ' ';
-        $out .= $date;
+        $out .= '<time datetime="' . $dateIso . '">' . $dateLocal . '</time>';
         if ($INFO['editor']) {
             $out .= ' ' . $lang['by'] . ' ';
             $out .= '<bdi>' . editorinfo($INFO['editor']) . '</bdi>';