lib/conn: handle preliminary responses via event callbacks
lib/conn: handle preliminary responses via event callbacks

Move reconnect, redirect and request-reissue logic into the request
completion path, so that elasto_conn_op_txrx() becomes a simple
dispatch-and-wait-in-event-loop.

Signed-off-by: David Disseldorp <589a549dc9f982d9f46aeeb82a09ab6d87ccf1d8@suse.de>

ddiss/elasto,ddiss/elasto