Use Title: meta instead of explicit <h1>

Author: tantek

css-ui-3/Overview.bs

@@ -1,10 +1,10 @@
 <style>
 dt[style*="cursor"] * { cursor: inherit; }
 </style>
-<h1>CSS Basic User Interface Module Level 3 (CSS3 UI)</h1>
 <style>#awesome-table td {padding:5px}</style>
 
 <pre class='metadata'>
+Title: CSS Basic User Interface Module Level 3 (CSS3 UI)
 ED: https://drafts.csswg.org/css-ui/
 TR: https://www.w3.org/TR/css3-ui/
 Previous Version: https://www.w3.org/TR/2017/CR-css-ui-3-20170302/