Update SolidFire Volume driver

Adds support for clone volumes and set QoS use volume type / extra_specs.
Also includes some minor cleanup and some hardening for known pre-release
XDB issue in SolidFire Cluster API.

Change-Id: I4b39b301b9a1f9b859a694decfee48c74d22a74a
Merge "Update SolidFire Volume driver"