Switch to using systemd configurations to manage radosgw instances;
the radosgw init script is obsolete and will be removed at some
point in time, and the newer style of managing radosgw daemons is
inline with current best-practice.
This changeset also changes the way cephx keys are issues; before
all rgw instances shared a key, now a key is issued per host.
The key is named 'rgw.`hostname`' to identify the application
and host using the key.
Existing deployments using the radosgw init script will be switched
to use the new systemd named units; this occurs once the new key
for the unit has been presented by the ceph-mon cluster over the
mon relation. A small period of outage will occur as the radosgw
init based daemon is stopped and disabled prior to the start of
the new systemd based radosgw unit.
This commit also includes a resync for charmhelpers to pickup
support for '@' in NRPE service check names.
Change-Id: Ic0d634e619185931633712cb3e3685051a28749d
Depends-On: I289b75a2935184817b424c5eceead16235c3f53b
Closes-Bug: 1808140
2858f1b02d