NetApp storage service feature support

This change introduces storage service feature for
NetApp drivers. It reports back supported service
features like mirroring, deduplication, compression
etc. to the scheduler which can be used to shortlist
backends. It accepts extra_specs defined
in volume type with the service features and provisions
volumes based on the requested spec.

blueprint cinder-nfs-driver-qos

Change-Id: I0706af2fe39b2db111a6d98b016307fc63f74dc6