Goal: 

• Test that setting limits on number of concurrent backup operations works as documented

Acceptance Criteria:

Verify the 4 scenarios

1) Eventlet semaphore
backup_workers=1
backup_max_operations=1

Trigger N backup and M restore operations - only see 1 happening at a time

2) Multiprocessing semaphore
backup_workers=2
backup_max_operations=1

Trigger N backup and M restore operations - 2 operations happening at a time

3) Eventlet Semaphore
backup_workers=1
backup_max_operations=2

Trigger N backup and M restore operations - 2 operations happening at a time

4) Multiprocessing semaphore
backup_workers=2
backup_max_operations=2

Trigger N backup and M restore operations - 4 operations happening at a time