Feat/manage subdirs via module files

Hello Vaidas. I've been using Puppet with Hiera to manage my own environments (with Vagrant and to build physical Hadoop clusters) for a while now and I've decided to use Puppet to manage remote Puppet servers. I found your module and was drawn to it because it's clean and uses Hiera. I extended it to allow me to pull in /etc/puppet/{hieradata, environments} from directories of the same name in the files section of the module. Based on the existence of this directory, I suspect you were planning to do the same. I also added /etc/puppet/graphs since I use that. 

Another idea, which is useful, but would take more time, would be to use Hiera to configure the module to create a Puppetfile per environment (i.e. /etc/puppet/environments/{environment}/Puppetfile) and then use librarian-puppet to populate the module directory. That has obvious tradeoffs too.

Anyway, thanks for the module. If you'd like to collaborate a bit on this, let me know.