Change daemon variable & simplify some option code

Change daemon variable & simplify some option code

- Rename daemon_over_rsh -> daemon_connection since it is also used to
  indicate if a non-rsh daemon connection is active.
- Move the daemon-over-rsh exception out of server_options() to the one
  caller that needs that behavior.
- Don't allow noop_io_until_death() to be short-circuited when talking
  to a daemon over a socket, because it can't send errors via stderr.