[do not merge] refs #3272 - print new user/password after installation

Review only, paired with https://github.com/theforeman/puppet-foreman/pull/190.

The change to print the details all the time might be needed if we had a partial failure, but enough that the web UI works - so as not to leave the user with no idea what their credentials are.  I will test this a bit more and perhaps try to improve how it's displayed.