Enable tox to upgrade packages if needed
Enable tox to upgrade packages if needed

Though it will take a bit more time, with this, running tox will upgrade
the packages to a later version if needed.

Change-Id: Iaf287d67e75189dc44760c477d880228a7d16c23

cneill/barbican,cneill/barbican,MCDong/barbican,openstack/barbican,openstack/barbican,MCDong/barbican,jmvrbanac/barbican,cloudkeep/barbican,cloudkeep/barbican,jmvrbanac/barbican