fixes#4555
- There's no easy way to declare an XSL with the node xml module, so I
needed to move the declarations to both be strings
- Ideally the code to serve the XSL would also be inside the sitemap
module, but I think we need to refactor a bit to get there easily
- Added the XSL from #4559, with minor amends to make the tables and urls
display correctly
Closes#623
- Add basic init and eventing scaffold
- Add sitemap-index.xml generation
- Broke out generators to individual files, added request handler
- Add page, author and tag xml files; add index mapping
- Add SiteMapManager unit tests
- Add Generators tests
- Cache invalidation headers for sitemap-*.xml
- Redirect sitemap.xml to index and rename to sitemap-index
- Handle page convert and publish/draft changes
- Add very basic functional test for route existence
- Add cache headers to sitemap routes
