Address issue #632 with systemd unit rename
Address issue #632 with systemd unit rename

* the client-name is actually `rgw.{{ ansible_hostname }}` instead
  of just `{{ ansible_hostname }}`
* it matches the directory created under `/var/lib/ceph/radosgw`
* and, it matches the client-name used to create the keyring in
  `pre_requisite.yml`

font/ceph-ansible,mcsage/ceph-ansible,ceph/ceph-ansible,guits/ceph-ansible,rootfs/ceph-ansible,travmi/ceph-ansible,WingkaiHo/ceph-ansible,bengland2/ceph-ansible,travmi/ceph-ansible,mcsage/ceph-ansible,albertomurillo/ceph-ansible,guits/ceph-ansible,jtaleric/ceph-ansible,WingkaiHo/ceph-ansible,jtaleric/ceph-ansible,jsaintrocc/ceph-ansible,ceph/ceph-ansible,WingkaiHo/ceph-ansible,jfcoz/ceph-ansible,font/ceph-ansible,jfcoz/ceph-ansible,albertomurillo/ceph-ansible,albertomurillo/ceph-ansible,fgal/ceph-ansible,fgal/ceph-ansible,verdurin/ceph-ansible-1,bengland2/ceph-ansible,dang/ceph-ansible,verdurin/ceph-ansible-1,jsaintrocc/ceph-ansible,dang/ceph-ansible,rootfs/ceph-ansible