Only enable auth_token in swift with keystone

We don't need to enable auth_token in pipeline when we don't have
keystone enabled.

Change-Id: I4695817766fc39fcceed32f71156d4123d5bdfa1
Install oslo.i18n from source

Add a step to install oslo.i18n from source.

Change-Id: Ie041d4b82ca75a1c2ff99563a7a87447adc57ad2
Merge "Only enable auth_token in swift with keystone"
Merge "Install oslo.i18n from source"
Merge branch 'master' of https://github.com/openstack-dev/devstack