Sync with global requirements
Sync with global requirements

There are still some problems with requirements updates proposal script,
so, syncing requirements manually.

* bump pbr to >=0.6,<1.0

Change-Id: Ibac6d4971debad1c477a07a6e9ce220865c48ca1

openstack/sahara-extra,openstack/sahara-extra,openstack/sahara-extra,openstack/sahara-extra