Release notes generator script (#250)
Release notes generator script (#250)

This PR adds a `release-notes.sh` script to generate release notes
and documents how to use it.

Signed-off-by: Pierangelo Di Pilato <b6054fff5975a97a6b1347c22e6e7915c701af4c@gmail.com>
knative-sandbox/eventing-kafka-broker,knative-sandbox/eventing-kafka-broker,knative-sandbox/eventing-kafka-broker