Allow the puppet_gem provider to use our cache
Allow the puppet_gem provider to use our cache

`/opt/puppetlabs/puppet/bin/gem` will not use `/root/.gemrc` or `/etc/gemrc`. This commit allows the vendored gem command to use the cache and work offline.
samuelson/pltraining-bootstrap,puppetlabs/pltraining-bootstrap,joshsamuelson/pltraining-bootstrap,kjhenner/pltraining-bootstrap,samuelson/pltraining-bootstrap,kjhenner/pltraining-bootstrap,puppetlabs/pltraining-bootstrap,kjhenner/pltraining-bootstrap,samuelson/pltraining-bootstrap,puppetlabs/pltraining-bootstrap,joshsamuelson/pltraining-bootstrap,binford2k/pltraining-bootstrap,binford2k/pltraining-bootstrap,joshsamuelson/pltraining-bootstrap,binford2k/pltraining-bootstrap