DOESN'T COMPILE - this push is just to remember this bug so find a clever solution in the future

File "simulator.ml", line 65, characters 23-617:
Error: Signature mismatch:
       ...
       Values do not match:
         val unicast :
           [ `Client | `Node of IntID.t ] ->
           MonoTime.t ->
           (MonoTime.t, IntID.t, 'a, 'a) event ->
           (MonoTime.t, IntID.t, 'a, 'a) t
       is not included in
         val unicast :
           [ `Client | `Node of IntID.t ] ->
           MonoTime.t ->
           (MonoTime.t, IntID.t, State.t, Client.t) event -> EventList.item
       File "simulator.ml", line 36, characters 4-127: Expected declaration
       File "simulator.ml", line 67, characters 4-11: Actual declaration
Command exited with code 2.