NetApp unified driver implementation.

NetApp has growing number of multiple drivers depending on storage families
and technologies. NetApp unified driver simplifies configuration
and provides single entry point for all storage technologies/drivers.
It provides new mechanism to support multiple NetApp technologies
and block drivers related to them. Deprecated 7mode dfm and c mode
webservice based drivers.

blueprint netapp-unified-driver

Change-Id: Ife3cb12ef2256e0124c9a02a968c20a580b5df93
Merge "NetApp unified driver implementation."