Preparitory work for implementing an acknowledgement queue. Commit for
backup/rollback before I modify PassageTest1Event to include a
RabbitMQMsgAck object.
Introduced RabbitMQMsgAck objects and propagated them from the consumer
helper bean to the @Observes method of the message handler that receives
the CDI event.

Next, I must change the producer message blocking queue treatment so
that both the outgoing serialized protobuf message as well as its
associated RabbitMQMsgAck object is placed in this queue so that the
producer threads can not only publish the message, but also palce the
RabbitMQMsgAck object in the message acknowledgement queue.
Implemented processing the acknowledgment queue in the consumer threads

Still need to implement offering entries to the acknowledgement queue
during message processing and publishing.
Started implementation of separate acknowledgment queues for each
consumer thread.

I must rip out everything to do with a single shared acknowledgment
queue and then finish the implementation of separate queues.
Finished implementing acknowledgement-after-send with one
acknowledgement queue per consumer thread.

Throughput is very low unless I inscrease basicQOS from 1 to perhaps 10
or so. I must still investigate this and consider making this parameter
depend on the acknowledgement mode.
The prefetch count passed to Channel.basicQos is now dependent on the
acknowledgement mode.
Finished implementing message acking/nacking after the outgoing message
is published.
Merge branch 'feature/consumer-acks-nacks' into develop