ensure pcs resource create commands run on just one node

We want to avoid getting unlucky and running the exact "pcs resource
create" command on two nodes at once which can destabilize pacemaker
(although this is not a problem upstream).  So, this commit adds a
parameter, cluster_control_ip as the one IP to run "pcs resource
create" commands from.
Merge pull request #215 from cwolferh/run_pcs_resource_from_chosen_node_only

ensure pcs resource create commands run on just one node