BUG-5685: Register BGP Peer Cluster Singleton Service

BUG-5685: Register BGP Peer Cluster Singleton Service

Register BGP Peer Cluster Singleton Service.
When running on clustering, it was need it to have
different configuration per instance to avoid conflicts.
Now all instance can have same configuration,
since cluster service provider take cares of make active
the one is running on Leader Cluster. If Leader goes down,
the instance from the new Leader will become active.

Change-Id: Ia4a95123e50fcb962c217b21967acf5a8820727d
Signed-off-by: Claudio D. Gasparini <cgaspari@cisco.com>
(cherry picked from commit 259daaeb2ad7ebf70308abc0a098ab2ba096b375)