(Lines #70-77)
I really like the idea of this feature, but this feels a bit "tacked-on" to me.  I'm sitting here thinking about it, and the more I do, the more I think that it would be better served by implementing a html_wrapper keyword. Have that setting take a template name, that the user could create in their views dir, with the token <% sitemap %> where they want it, and use that to interpolate the generated HTML into.