Create pem key directly
Create pem key directly

No need to use the shell for simple ruby code when creating the
pem key.

Change-Id: I60ffb6941e187abcc33f4fbe408a87be5c81f9c8
Closes-Bug: #1459695

mohitsethi/openstack-chef-repo,apealive-cookbooks/openstack-chef-repo,apealive-cookbooks/openstack-chef-repo,Kmotiko/openstack-chef-repo,kevinlowrie/openstack-chef-repo,AlphaStaxLLC/openstack-chef-repo,mohitsethi/openstack-chef-repo,kevinlowrie/openstack-chef-repo,AlphaStaxLLC/openstack-chef-repo,Kmotiko/openstack-chef-repo