Azure Storage sprint 40: support sas token used in operations and get/set service properties

Azure Storage sprint 40:

- Support sas token to be used in blob, file, table and queue operations by parameter --sas or --source-sas/--dest-sas (blob copy)

- Support get and set storage service logging properties

- Support get and set storage service metrics properties
Consider a named constant instead of literal "2" - no idea what it means here.