Splitted administration and normal web site interfaces.

This optimises a bit the routing map, and make cleaner separation.
Make the base url for admin pages customizable via `administration.base_path` variable in cms.ini
   note: could be /admin, /roc-admin, or ..
It is possible to have a specific theme for administration via the variable "administration.admin"

modules/sitemap/cms_sitemap_module.e

@@ -75,7 +75,7 @@ feature -- Handler
 			d: HTTP_DATE
 		do
 			create {GENERIC_VIEW_CMS_RESPONSE} r.make (req, res, api)
-			create l_cache.make (api.files_location.extended ("modules").extended ("sitemap").extended ("sitemap.xml"))
+			create l_cache.make (api.cache_location.extended (name).extended ("sitemap.xml"))
 			if
 				l_cache.exists and then
 				not l_cache.expired (Void, 24*60*60) -- 1 day