Added keystone auth port to the nova config

Added the $KEYSTONE_AUTH_PORT to the keystone_authtoken
section of the create_nova_conf function.
This is required as without it nova doesn't communicate
to the keystone server. Generating an "Unauthorised (HTTP 401)"
page when acceesing /admin/.

Change-Id: Ibf4d9d1c21081a1e3de4ea765f4db6de5fbdb237
Merge "Added keystone auth port to the nova config"