- Move closing of servlink control fd to close_connection()
instead of doing it in exit_local_server(), and make sure
we first close the data fd and then the control fd.
- Have servlink process ready fds in order net, data, ctrl
instead of ctrl, data, net. This seems to fix the problem
that squit reasons do not show up on the other side of a
ziplink (by making it send any final SQUIT and/or ERROR
before noticing the closed control fd).
