better readme

Author: simplesteph

README.md

@@ -129,3 +129,6 @@ docker-compose -f zk-multiple-kafka-multiple.yml down
 
 Q: Kafka's log is too verbose, how can I reduce it?
 A: Add the following line to your docker-compose environment variables: `KAFKA_LOG4J_LOGGERS: "kafka.controller=INFO,kafka.producer.async.DefaultEventHandler=INFO,state.change.logger=INFO"`. Full logging control can be accessed here: https://github.com/confluentinc/cp-docker-images/blob/master/debian/kafka/include/etc/confluent/docker/log4j.properties.template
+
+Q: How do I delete data to start fresh?
+A: Your data is persisted from within the docker compose folder, so if you want for example to reset the data in the full-stack docker compose, first do a `docker-compose -f full-stack.yml down`, then remove the directory `full-stack`, for example by doing `rm -r -f full-stack`.