real instance object like IContent, this will dramatically increase performance for bulk publishing when not
in a load balanced environment. Updated methods on DistributedCache to refresh many instances at one time, this also
means we're not re-looking it back up again. Need to update media, users, templates, members and macros to use this new feature too.
old ICacheRefresher but now we can plugin 2 new providers - one for resolving a list of servers and the other to notify the servers of changes.
By default we have the configuration based providers which uses the umbracoSettings.