Implement retype in HP LeftHand driver

This adds the ability to modify the
type of an existing HP LeftHand volume to
another type supported on the same backend.

Main use case for this is changing provisioning,
(full vs. thin), adaptive optimization and data
protections settings for a volume on-demand.

Change-Id: I78e53431708bcb3151c5dc4016e65d1a655e03c6
Implements: blueprint retype-support-for-hplefthand-driver
Sync request_id, request_utils for cinder

This is in preparation for work being done on request ID tracing across
OpenStack services.

Per discussion in blueprint cross-service-request-id , the standard header
name for the request ID across OpenStack projects should be
x-openstack-request-id. The request_id middleware was created for just this
purpose, as oslo change Ic7967cd62e7b743343d70f751b9238339171e013 . Using the
same middleware allows for consistency across projects.

There is an additional oslo module, request_utils, introduced as
change Id085c4444fee2bb68b80738bfe77ccb0ba1908ec to allow uniform logging of
request IDs. Bring that in as well so we have it when necessary.

Implements: blueprint add-standard-req-id-header
Change-Id: If080df2a323347924c93a912538dab5ffeffe982
Ensures NetApp iSCSI driver correctly compares int values for size

The NetApp iSCSI driver needs to verify that the new size requested
during an extend operation does not exceed the max_resize of the
lun.  However, the driver was doing a >= compare against str values
of the sizes rather than the int values.  This caused the incorrect
code path to be used in certain situations.

Change-Id: I8bc66c71db6b469c7adf00ce8b5091513fccb740
Closes-Bug: 1281279
Merge "Implement retype in HP LeftHand driver"
Merge "Sync request_id, request_utils for cinder"