Merge branch 'ansible-user' into 'master'

Have cobbler create a cm user for ansible to use

In the PR with the ubuntu port, I create the teuthology_user for every distro so we have that covered.  I'm thinking I could probably write a simple playbook to create this cm user for any existing nodes that haven't be reimaged with the new kickstarts.  That'd be nice so we could start fixing ssh keys with ansible and change the default ansible_user in ansible.cfg.