* validate X-Druid-Task-Id header in request and add header to response
* modify KafkaIndexTaskClient to take a TaskLocationProvider as the TaskLocation may not remain constant
segment creation deterministic.
This means that each segment will contain data from just one Kafka
partition. So, users will probably not want to have a super high number
of Kafka partitions...
Fixes#2703.
Reads a specific offset range from specific partitions, and can use dataSource metadata
transactions to guarantee exactly-once ingestion.
Each task has a finite lifecycle, so it is expected that some process will be supervising
existing tasks and creating new ones when needed.