Rename replication subscription to replication session

Also rename replication subscriber to slave and publisher to master.
Rename subscribe/unsubscribe to open session/close session
Configurable replication API version support (legacy or not).

Default is legacy.
Reverted string interpolation in ConsistencyMasterSlave

We are not ready to drop support for scala 2.9 yet!
Merge pull request #219 from wajam/manu-replication-session

Rename replication subscription to replication session