Finally fixed all of the horrendus bugs and issues in routing:
- RemoteClientManagers now use the global routing table in server by
  default.
- Fixed an issue with routers not also properly dealing wit being
  endpoints.
- SelectorThreads now check if a newly-registered client can write
  immediately.
- Requests can now have request responses, rather than the silly local
  routing that was going on.
- Clients no longer deal with requests at all - use a client manager for
  this. (Will probably change later again to allow for Client-only
  implementations).