kill UmbracoWebsiteSecurityFactory and UmbracoRoutedRequest, simplify all this.

src/Umbraco.Core/Security/IUmbracoWebsiteSecurityAccessor.cs

@@ -1,7 +1,7 @@
-namespace Umbraco.Cms.Core.Security
+namespace Umbraco.Cms.Core.Security
 {
     public interface IUmbracoWebsiteSecurityAccessor
     {
-        IUmbracoWebsiteSecurity WebsiteSecurity { get; set; }
+        IUmbracoWebsiteSecurity WebsiteSecurity { get; }
     }
 }