Enable oslo.db testing on python 3.3
Enable oslo.db testing on python 3.3

We suppose to add python 3.3 support to oslo.db so we should enable
(as non-voting, at first) gate testing on python 3.3

Change-Id: I413cf53234536286a6718e7662b7698f5ef4f64b

dongwenjuan/project-config,anbangr/osci-project-config,citrix-openstack/project-config,open-switch/infra_project-config,coolsvap/project-config,dongwenjuan/project-config,openstack-infra/project-config,noorul/os-project-config,anbangr/osci-project-config,noorul/os-project-config,osrg/project-config,openstack-infra/project-config,citrix-openstack/project-config,Tesora/tesora-project-config,Tesora/tesora-project-config,coolsvap/project-config,open-switch/infra_project-config,osrg/project-config