do not merge -- fencing refactor

Posting the PR to give folks an idea of where this is going.  For sure, we want to move stonith out of common.pp.  What is less sure is the pattern to follow near and longer term for supporting additional fencing types in puppet-pacemaker (not there are 30 fencing types available there right now).  A couple of options are outlined here: https://github.com/cwolferh/astapor/blob/2d8f9c9890d9465172a61d5c5352f5acaed30f92/puppet/modules/quickstack/manifests/pacemaker/stonith.pp#L68