Update README and add undeploy to Makefile

[jogrogan]

Reformatted Makefile to group deploy/undeploy commands.
Added undeploy-dev-environment target to Makefile to remove all of the Kafka/Flink resources in the correct order.

Exposed a new internal port via Kafka to allow use of the Kafka CLI to produce/consume messages:

  $ kubectl -n kafka run kafka-producer -ti --image=quay.io/strimzi/kafka:0.44.0-kafka-3.8.0 --rm=true --restart=Never -- bin/kafka-console-producer.sh --bootstrap-server one-kafka-bootstrap:9094 --topic my-topic
  $ kubectl -n kafka run kafka-consumer -ti --image=quay.io/strimzi/kafka:0.44.0-kafka-3.8.0 --rm=true --restart=Never -- bin/kafka-console-consumer.sh --bootstrap-server one-kafka-bootstrap:9094 --topic my-topic --from-beginning

[ryannedolan]

neat!