Docker ansible host (#742)
Docker ansible host (#742)

* Document using a Docker image for Ansible host

* Fix the markdown url syntax

* Mention keystonerc as well

cwilkers/openshift-ansible-contrib,dav1x/openshift-ansible-contrib,glennswest/openshift-ansible-contrib,Tlacenka/openshift-ansible-contrib,cwilkers/openshift-ansible-contrib,Tlacenka/openshift-ansible-contrib,pschiffe/openshift-ansible-contrib,openshift/openshift-ansible-contrib,pschiffe/openshift-ansible-contrib,pschiffe/openshift-ansible-contrib,dav1x/openshift-ansible-contrib,openshift/openshift-ansible-contrib,dav1x/openshift-ansible-contrib,cwilkers/openshift-ansible-contrib,Tlacenka/openshift-ansible-contrib,openshift/openshift-ansible-contrib,Tlacenka/openshift-ansible-contrib,pschiffe/openshift-ansible-contrib,cwilkers/openshift-ansible-contrib,openshift/openshift-ansible-contrib,dav1x/openshift-ansible-contrib