Updated openstack/openstack
Project: openstack/nova  852e9c3537a81660cde5028e713c558abecdb2f9

xenapi: refactor volumeops attach

Refactor the attach code, so its more readable.

At the same time, add some new unit tests to better cover the volume
attach code.

In a later patch we will remove the older mox tests, and dead code that
is now only left in volumeops to keep those old tests running.

Change-Id: Ic50dba5588bb968eca3ac2bf94c3eb719fa2cf6b