Use Title: meta instead of explicit <h1>

Author: tantek

css-pseudo-4/Overview.bs

@@ -1,6 +1,5 @@
-<h1>CSS Pseudo-Elements Module Level 4</h1>
-
 <pre class='metadata'>
+Title: CSS Pseudo-Elements Module Level 4
 Shortname: css-pseudo
 Level: 4
 Status: ED