Added Qualifiers to ensure each consumer thread gets itsown helper EJB
Implemented qualifiers for selecting helper singleton bean 1 and 2.

Also implemented "Alternatives" so that the helper singleton EJB
implementations can be specified in beans.xml.
Renamed classes so that their implementation use case is clear.
Eliminated an unused constructor
Moved most code from RabbitMQConsumer into
MessageConsumerHelperImageTest to make it ieasier to support different
message consumer implementations using CDI "alternatives".