KIP-431 — Support of printing additional ConsumerRecord fields in DefaultMessageFormatter

Accepted Kafka 2.7 ConsumerAdmin

Adds `print.offset`, `print.partition`, `print.headers`, and related formatting options to the `DefaultMessageFormatter` in `kafka-console-consumer.sh`. The console consumer currently can only print key, value, and timestamp—fields like partition, offset, and headers require file-system access to the broker (via `kafka-dump-log.sh`) or external tools like `kafkacat`.

Details