What's new in version 1.9.0

Upgrade of kafka-clients from version 1.0 to 2.1.1. For the consumer and producer configuration, please consult the Consumer Configs or Producer Configs section of the Apache Kafka 2.1 documentation.
The MessageHubProducer can now be flushed after a fixed number of tuples, new optional parameter flush.
Bug fix: MessageHubConsumer can create invalid checkpoint when group management is active. When Kafka's group management is used in a consistent region, the maxConsecutiveResetAttempts should be increased (default value is 5).