Updated openstack/openstack
Project: openstack/glance_store  4bd501f957a1b2866a856cca79fccd6f0f13500b

Use oslo.serialization

Module `jsonutils` from common code was graduated to oslo.serialization,
so it would be great if we reuse this library.
Remove unused log.py and fileutils.py

Change-Id: Ie7d80df501296b4b06da8c1cc155bcc4b64bfe28