Add dedup provisioning to 3PAR drivers

Add dedup provisioning to 3PAR drivers

3PAR now supports thin duplication provisioning. This review is for
adding the dedup provisioning support to the 3PAR provisioning extra
specs type as well as supporting volume retype between provisioning
types (thin<->dedup, full<->dedup).

The OpenStack Configuration Reference Guide will need to updated
to include dedup as a valid hp3par:provisioning value. A note
should also be added that this feature requires SSD disks and
3PAR firmware version 3.2.1 MU1 or greater.

DocImpact
Implements: blueprint 3par-dedup

Change-Id: I6ebad3682d5d53a9b1a6329d666a1d7fb06eba0a