Sync common modules from Oslo

Oslo version:
commit  569979adfd4237869bb50c7aaa02bc3fd4f0b413
Author: Author: Romain Soufflet <romain@soufflet.io>
Date:   Wed Jul 9 10:45:59 2014 +0200
Name:   Fix tests.unit.reports.test_base_report with python3.4

Except update of oslo code updated file 'openstack-common.conf'
that is used for automated update, see following:
https://wiki.openstack.org/wiki/Oslo#Syncing_Code_from_Incubator

Change-Id: I659d0ceee14d69b02743c829e27fec042a38d7e5