Initial DT workflow

Sample PPPoE-based workflow.
Track the subscriber PPPoE protocols state, authentication and IP address assignement are done via PPPoE protocols (PAP, CHAP, IPCP...).
Work with BNG app running on ONOS that generates events in the bng.pppoe Kafka topic.

Change-Id: Iae57395dcc90d027932c790c1c36d7b3e3f3e19b
32 files changed