Sitemap

Sitemaps with an index sitemap and sub-sitemaps pointing to public published channels, posts, and tags. Things requiring a user to follow will not show up. I still have to figure out how to and what to test with this branch, but it does create a sitemap that complies with Google News Sitemap's requirements. 
This could be a good guide to use: https://github.com/callowayproject/django-news-sitemaps/blob/master/news_sitemaps/templates/sitemaps/news_sitemap.xml