hgweb: use the given revision in the name of the archive
If you ask for an archive in hgweb by tagname the directory in the archive
should include the tagname not the changeset-id.
#header#
<title>Mercurial repositories index</title>
</head>
<body>
<h2>Mercurial Repositories</h2>
The specified repository "#repo|escape#" is unknown, sorry.
Please go back to the main repository list page.
#footer#