objecter: set op->paused in recalc_op_target(), resend in not paused

When going through scan_requests() in handle_osd_map() we need to make
sure that if an op should not be paused anymore then set it on the op
itself, and return NEED_RESEND. Otherwise we're going to miss reset of
the full flag.
Also in handle_osd_map(), make sure that op shouldn't be paused before
sending it. There's a lot of cleanup around that area that we should
probably be doing, make the code much more tight.

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