Cinder introduced new attachment API flow in microversion 3.27
(also attachment_complete added in mv 3.44 and support for passing
mode added in mv 3.54) which provides a clean interface to
interact with cinder for attachments and is also required for
multiattach volume support (Related future work).
Nova uses it since a long time and is proven to be stable,
this patch implements the same for glance.
The create volume and delete volume calls are also moved to
cinder_utils file to use the generic exception handler
and keep similar code together for consistency.
Partially Implements: blueprint attachment-api-and-multiattach-support
Change-Id: I2758ed1d5b8e0981faa3eff6f83e1ce5975a01d2
1178f113c4