rgw_zone: Collect RGWRados administrative operations.

Collect operations for garbage collection, log display, log removal.
pool creation, pool deletion, and zone info, zone set.

Signed-off-by: caleb miles <caleb.miles@inktank.com>
rgw: Add RESTful zone administration operations.

Add RESTful operations for getting zone info, showing logs, removing logs,
adding placement pools, removing placement pools, listing expired garbage
collection objects, and manually collecting expired garbage collection
objects.

Signed-off-by: caleb miles <caleb.miles@inktank.com>
rgw_user: Code cleanup.

Signed-off-by: caleb miles <caleb.miles@inktank.com>