Implement startup and shutdown sequence of jobs in ZK environment

Problem that we need to solve is: Do we need multiple job attempts in the ZK tree? If yes, who creates the persistent subtrees? There is no leader until the ZK trees are setup.

In the initial prototype, the first processor instance creates the ZK hierarchy. If we were to support multiple job attempts, then we need different ZK trees for each attempt. How do all the processors within a job know which the attempt ID to join?