Remove empty strings from resource containment paths?

When Puppet generates the containment path for a resource, it often includes an empty string as a discrete element in the path following the 'Stage' resource. I suspect that this is a bug in puppet, and should be fixed; but we may need to also fudge this out of the data in the puppetdb terminus code in order to maintain compatibility with older versions of puppet.

Need to open a corresponding ticket for puppet itself and discuss with someone on the OSS team.