rgw: cls_log_trim boundary change

end_time is not inclusive

Signed-off-by: Yehuda Sadeh <yehuda@inktank.com>
rgw: metadata rm

Still needs to fix the way we remove user entries; need to take
different path, similar to put_entry())

Signed-off-by: Yehuda Sadeh <yehuda@inktank.com>