cls_rgw: update olh log when unlinking entry

Need to update log so that later client will be able to appropriately
remove the object.

Signed-off-by: Yehuda Sadeh <yehuda@redhat.com>
cls_rgw: unlink object instance

Signed-off-by: Yehuda Sadeh <yehuda@redhat.com>
rgw: unlink obj instance

use new objclass method

Signed-off-by: Yehuda Sadeh <yehuda@redhat.com>
a fix (squash)

Signed-off-by: Yehuda Sadeh <yehuda@redhat.com>
rgw: follow olh where needed

Signed-off-by: Yehuda Sadeh <yehuda@redhat.com>
cls_rgw: keep null-versioned object as versioned object

when olh is created. Mark the object as such, so that we'll know to
handle it correctly. This is needed so that we could handle the 'null'
version as required.
Still doesn't work correctly.

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