convert: make contents of "extra" dict available from sources, for sinks.
This breaks hash preservation for hg->hg conversion, as each converted
change gets a convert_revision item added to its extra dict. Ugh.
#header#
<title>#repo|escape#: tags</title>
<link rel="alternate" type="application/atom+xml"
href="#url#atom-tags" title="Atom feed for #repo|escape#: tags">
<link rel="alternate" type="application/rss+xml"
href="?cmd=tags;style=rss" title="RSS feed for #repo|escape#: tags">
</head>
<body>
<div class="buttons">
<a href="?cl=tip">changelog</a>
<a href="?sl=tip">shortlog</a>
<a href="?mf=#node|short#;path=/">manifest</a>
<a type="application/rss+xml" href="?cmd=tags;style=rss">rss</a>
<a type="application/atom+xml" href="#url#atom-tags">atom</a>
</div>
<h2>tags:</h2>
<ul id="tagEntries">
#entries%tagentry#
</ul>
#footer#