Added (very basic) spam filtering plugin support. Plugins can mark a message as spam by hooking into the spam check API, which is documented in functions.php. No spam checking functionality is built-in.
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<title>blank_page</title>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />
<script type="text/javascript">
parent.TemplateDialog.loadCSSFiles(document);
</script>
</head>
<body id="mceTemplatePreview" class="mceContentBody">
</body>
</html>