Merge branch 'initial-playbook' into 'master'

Create a playbook to run for initial node setup.

This playbook is meant to be pointed at a node after it's been freshly created.  It will ensure that the node is setup to be managed by ansible and then provision it according to it's role set in the hosts file.

All I've included now is the testnodes.yml playbook, but we could include cobbler.yml and any future playbook we write here.  Playbooks will be skipped that don't match up with the current host being provisioned.  For example, if we add cobbler.yml to this playbook and run it against a testnode the cobbler setup would be skipped because it is not in the 'cobbler' group which constrains the plays in cobbler.yml.