BarrierMessageHandler should support separate timeouts

[micheljung]

In BarrierMessageHandler, there are two scenarios:

1. The request message arrives before the trigger message
2. The trigger message arrives before the request message

Expected Behavior

The timeouts should be configurable individually.

Current Behavior

Only one timeout can be set which applies for both.

Context

For instance, if an HTTP request sends a message to the barrier, it should time out after 1min if no trigger message is received. If the trigger message then arrives late and the HTTP request is no longer waiting, it shouldn't wait for 1min before discarding the request but do so immediately.

I haven't found an alternative to BarrierMessageHandler that allows me to block until a response message is received, which is delivered asynchronously.