Implemented the following commands:
1. list-batch-jobs command. This command takes an optional jobName as argument. If no jobName is specified, then all batch jobs are listed. The --long option can be used to find out the start-time, end-time, instanceId, executionId etc.
2. list-batch-job-executions can be used to list job executions based on either instanceId or executionId. --long option can be used to list batch-status, exit-status, job-parameters step-count etc.
3. list-batch-job-steps can be use to list the status of every step in a job-execution. Again, --long can be used to retrieve step-status, step-exit-status, step-metrics etc.