This patch removes usage of incubated libraries from
neutron.openstack.common and starts "copying" such libraries from
the oslo incubator as any other project.
As vmware-nsx currently only uses i18n, and loopingcall, these are
the only modules added to openstack-common.conf
All the imports pointing out to neutron.i18n or
neutron.openstack.common.loopingcall are amended in this patch.
Closes-Bug: #1432783
Change-Id: I6b9d576bad33310598139c7169627c44014301af