OGS2:Intersim

Initial thoughts
Current XML-RPC lib is way too slow (As we've all learnt), but .NET remoting is not feasible for future interoperability.

Proposed solutions to discuss:
 * new XML-RPC lib
 * custom XML-over-HTTP protocol
 * custom TCP protocol
 * LL-type circuits over UDP

Note: We already use .Net remoting in Grid mode (although our remoting code certainly needs improving), and the current plan is to continue using that in the future.