Functional changes from Hammer federated configuration

In Jewel, you can configure each Ceph Object Gateway to work in an active-active zone configuration, allowing for writes to non-master zones.

The multi-site configuration is stored within a container known as a realm. It stores zones, zone groups, and a time period with multiple epochs for tracking changes to the configuration. In Jewel, the ceph-radosgw daemons handle the synchronization by eliminating the need for a separate synchronization agent. Also, the new approach to synchronization allows the Ceph Object Gateway to operate with an active-active configuration instead of active-passive.