[InterNetNews/inn] 75ecdf: Exit with status 0 when printing usage message

[Julien ÉLIE]

  Branch: refs/heads/main
  Home:   https://github.com/InterNetNews/inn
  Commit: 75ecdf06f79780469f38740deb96b961ac428041
      https://github.com/InterNetNews/inn/commit/75ecdf06f79780469f38740deb96b961ac428041
  Author: Julien ÉLIE <Julien-Elie at users.noreply.github.com>
  Date:   2023-01-24 (Tue, 24 Jan 2023)

  Changed paths:
    M backends/sendinpaths.in
    M contrib/backlogstat.in
    M contrib/thdexpire.in
    M control/controlchan.in
    M frontends/mailpost.in
    M frontends/pullnews.in
    M frontends/scanspool.in
    M innfeed/procbatch.in
    M innfeed/testListener.pl
    M scripts/innmail.in

  Log Message:
  -----------
  Exit with status 0 when printing usage message

Homogenize the exit status of INN programs when explicitly run with
a flag asking for printing their usage messages.  Status 0 should be
returned instead of 1.

Also, homogenize the format of the usage message.

This patch updates all Perl scripts using Getopt::Std.

see #254