Log (and maybe fail) exceptions returned by offset commit callback

[seglo]

Short description

When exceptions are passed to the offset commit callback they are passed back to the original committer as an ask response which will fail the stream. We should consider at least logging these exceptions, or shutting down the stream at the source instead.

Details

We should consider logging that these exceptions occur in the KafkaConsumerActor and consider failing the stream as well. The processErrors method of KafkaConsumerActor does both, perhaps it could be reused? In some cases we may receive KafkaExceptions that are recoverable (retriable). We could consider not propagating these exceptions and let the KafkaConsumer recover internally.