Changes and new Scripts that override dbsTest.py

functionality on dbsTest.py was splitted among 3 scripts:
dbs3Client.py: Uses the dbs3 api to query about datasets and events.
reqMgrClient.py: Queries related to request manager and workflows (that imply knowing workflow information)
WorkflowPercentage.py: To calculate and show the progress of a given workflow (from command line).