migrate from params to hiera module data

http://www.devco.net/archives/2013/12/08/better-puppet-modules-using-hiera-data.php
http://forge.puppetlabs.com/ripienaar/module_data

This is my first try at this, and I know it limits the module to puppet3
and above, but I'm fine with that at this point. puppet 3.4 is out for
crying out loud :)