'nethack --show' is rejected, which is ok, but the feedback is
'prscore: bad arguments (2)' which is pretty confusing.
Reject any --s unless it's the start of --scores or --showpath[s].
'nethack --show' will be rejected as "Unknown option: --show."
'nethack -show' is still accepted and will report that it can't find
any scores for how as it always has (assuming that there aren't any
score entries for "how" :-).
1b04533b35