Added a link with rel=index.

Author: bert-github

css-module/Overview.src.html

@@ -4,6 +4,7 @@
   <meta http-equiv="Content-Type" content="text/html; charset=utf-8">
   <title>CSS TEMPLATE Module Level N (CSS3 TMPL)</title>
   <link rel=contents href="#contents">
+  <link rel=index href="#index">
   <link rel="stylesheet" type="text/css" href="../default.css">
   <link rel="stylesheet" type="text/css"
         href="http://www.w3.org/StyleSheets/TR/W3C-[STATUS].css">