Change warning message in NetApp driver for vsadmin creds

The new warning messages explicitly lists the extra_specs that
can't be supported depending on the access level fo the creds
that were provided. Also corrects a spelling error for the
netapp_nodedup extra_spec.

Change-Id: I1b27d9f4043321a4812e4e457c32a1040676c8e5
Closes-Bug: 1284796
updating testing readme with more current information.

Change-Id: I3ef39f5484170c1886c3b88e81b42450339a0d39
Closes-Bug: 1277179
Merge "Change warning message in NetApp driver for vsadmin creds"
Merge "updating testing readme with more current information."