Provide a bin script to check consumer lag from KafkaSpout to Kafka topic offsets and integrate with storm ui

We store kafkaspout offsets in zkroot + id path in zookeeper. Kafka provides a utility and a protocol request to fetch latest offsets into topic

example:
bin/kafka-run-classh.sh kafka.tools.GetOffsetTool 

we should provide a way for the user to check how far the kafka spout read into topic and whats the lag. If we can expose this via UI even better.