Updated openstack/openstack
Project: openstack/requirements  3665900688e743b9aa1a24a250ff4a8312a108c3

add oslo.middleware

allow projects to use the new oslo.middleware instead of copying
from oslo-incubator.

Change-Id: Ief0940907423b0b2bb529fd29481d89d76b5ebc4
implements: blueprint graduate-oslo-middleware