2 optimizations on api-server startup:
 * Remove dead code for addr mgmt house-keeping setup (done lazily instead of startup)
 * ZK no longer is consulted on db_conn.fq_name_to_uuid lookup, so remove read/migrate
   info from Cassandra to ZK on startup

Change-Id: I20b59d27b2180cadfc5c6d47cde6c9b9d8f2e865
Merge "2 optimizations on api-server startup:  * Remove dead code for addr mgmt house-keeping setup (done lazily instead of startup)  * ZK no longer is consulted on db_conn.fq_name_to_uuid lookup, so remove read/migrate    info from Cassandra to ZK on startup"