I've spotted a problem with disabling the timeout; the node tracks each message it sends so that when a response comes back it can send the response in the context of the message that triggered it.
If we disable the timeout, then that state will still accumulate in the node, never being cleared - leaking memory.
I've come to the conclusion that:
- Link Call should not allow the timeout to be disabled - it always expects a response
- The Link Out node should have a dynamic mode added to it to satisfy the dynamic link without a response case
