update script should install released oslo.config

the update.sh script was still referencing a beta release off the
tarballs site, which ensured you were getting a terribly old
oslo.config. We should use a real version of oslo.config to do
updates.

Change-Id: Ia7a2c3d8e22d1d5d6afc01150ec87f3d54778606
Merge "update script should install released oslo.config"