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
the argument is continuationTokenIndexInArg which actually needs a int input, since in the SDK the continuation token para is in different index between different calls. so we cannot fill it in at the caller at a fix index. I changed to use a constants in StorageUtil to present that.