Update pacemaker service management and corosync calls.

NOTE: relies on https://github.com/radez/puppet-pacemaker/pull/24 (merged, needs to be in RPM)

RHEL 7 uses systemd, so switch our calls to use the new wrapper in
puppet-pacemaker, pacemaker::resource::service (wrapped in
quickstack::pacemaker::resource::service, since we need to only run commands
on one node - that support is not yet baked into the pacemaker module).