Updated openstack/openstack
Project: openstack/glance  1cdc555d21c532d7e4963ed1784a488769abdd1b

replace dict.iteritems() with six.iteritems(dict)

All metadata definition code added should ensure that
six.iteritems is used.

Change-Id: Ic93595ffb2a5a8ed7667028d820fac8debd988e6
Closes-Bug: #1370769