New issue 21 by jason.birch: Consider refactoring Sitemap representations
as children of representations
http://code.google.com/p/georest/issues/detail?id=21
Sitemaps are dependent on a specific representation (HTML, KML, etc). They
are currently maintained as a top-level representation, but are logically
more of an extension of a given representation. It may make sense to
enable them with an attribute of the representation
(sitemap="sitemap.xml.gz" OR sitemap="sitemap_geo.xml.gz" sitemapext="geo")
instead.