Add a stream.sh command to display consumer distribution

stream.sh can already display lag ant latency per stream.
it would be nice to visualize the distribution of consumer when using Kafka, something like:

• consumer group
  • host id
    • client id (consumer name)
      • list of topic partitions

So we can see how many consumers are running per host and how many partitions are assigned by consumer, this can be an easy way to check if the load is evenly balanced.

If we can have the lag per consumer it will be nice
if we can have a plantuml output it rocks.