Remove zone from zonegroup and update period before deleting the zone to avoid incons...

Remove zone from zonegroup and update period before deleting the zone to avoid inconsistent period information across other zones.

When you delete a zone without removing from zonegroup, the period update would
fail since that command needs to load the zone and zonegroup to be able to
update the master. Period update would fail with an error like this:

radosgw-admin period update --commit
-1 Cannot find zone id= (name=), switching to local zonegroup configuration
-1 Cannot find zone id= (name=)

Signed-off-by: Shilpa Jagannath <smanjara@redhat.com>