Add an entry to the container hosts file
Add an entry to the container hosts file

But gate it behind `$yum_cache` for now because we're not 100% certain it won't have side effects in other places
samuelson/pltraining-dockeragent,puppetlabs/pltraining-dockeragent,joshsamuelson/pltraining-dockeragent,binford2k/pltraining-dockeragent,samuelson/pltraining-dockeragent,puppetlabs/pltraining-dockeragent,binford2k/pltraining-dockeragent