Add tests for service Notifications

Add tests for service Notifications

- Add functional test test_nbinotifications.py to check the sending of
  service notifications when service-create and service-delete
  are invoked
- Update test_utils.py by adding a new function capable of getting the
  service notifications
- Add docker-compose.yml necessary for Kafka and ZooKeeper dockers
- Update tox.ini to include the new functional test and run
  Kafka/ZooKeeper dockers

JIRA: TRNSPRTPCE-343
Signed-off-by: Thierry Jiao <thierry.jiao@orange.com>
Change-Id: Ice4d8a2980317ee1dca6533752466305ed525981