This commit enables the control repo to use Hiera 5 environment-level
hiera hierarchy. This means adding a hiera.yaml to the repo, and moving
hieradata/ => data/.
We should do this to the control-repo template new customers base off of
because in a Hiera 5 world, the global hiera.yaml should be very minimal
(possibly even ONLY having the console level), and everything else
(nodes, common) belongs in the environment hiera.yaml.
This control-repo template is how people start using Puppet. It should
reflect using our most modern technologies.
