generalize RPC-like workflow
Just putting this here before I forget...
There are numerous cases in our models which we have an RPC-like event flow (execute event on server with x,y,z parameters, and when it is finished send back to me a completion event with a,b,c output parameters). It may be worth thinking how we can generalize this concept. The concept has overlaps with the message funneling currently used in LSM/modelnet/resource models, the tw_memory feature, and #28 (closed).