Throw on received message if the RoC of an all-nodes request has finished

[david-eckardt-sociomantic]

In several situations, including a node shutdown and client/node protocol mismatch, the client can receive a message for a request-on-conn whose fiber has already terminated. Throw a protocol error to initiate a shutdown to prevent RequestOnConn.setReceivedPayload from attempting to resume the terminated fiber.

Fixes #309.

[david-eckardt-sociomantic]

Updated, addressing @gavin-norman-sociomantic's comments. Added issue #311.