Install Guide: cinder setup for ceilometer fixes

* openstack-cinder-volume should be restarted, not
  openstack-cinder-agent-central
* use 'ceilometer' instead of 'cinder' in the section id

Change-Id: Id9cbab26ed8aa9d09b98da93576ff7aad8c304b7
Closes-Bug: #1259456
backport: havana
Merge "Install Guide: cinder setup for ceilometer fixes"