rgw: configurable chunk size

Fixes: #7589

Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
Signed-off-by: Yehuda Sadeh <yehuda@inktank.com>
Merge remote-tracking branch 'gh/firefly'
Merge pull request #1541 from onlyjob/debian

logrotate improvement: do not rotate empty logs

Reviewed-by: Sage Weil <sage@inktank.com>
logrotate: do not rotate empty logs (2nd logrotate file)

Signed-off-by: Dmitry Smirnov <onlyjob@member.fsf.org>