Manila cDOT qualified specs

Like Cinder, Manila has share_types that may contain qualified extra-specs, extra-specs that have significance only for the backend driver and which are not reported back to the scheduler. This blueprint is for work to implement the following qualified extra specs for the NetApp cDOT driver: netapp:thin_provisioned, netapp:dedup, and netapp:compression. The implementation will set these characteristics when creating the flexvol that backs a new manila share if that share is created with an share_type containing a qualified extra-spec for that characteristic that is set to 'true'.