[InterNetNews/inn] c3e5c1: Add new ovflushcount parameter in inn.conf

[Julien ÉLIE]

  Branch: refs/heads/main
  Home:   https://github.com/InterNetNews/inn
  Commit: c3e5c1c5781629ffaf477d9a4fe2a31172e081b2
      https://github.com/InterNetNews/inn/commit/c3e5c1c5781629ffaf477d9a4fe2a31172e081b2
  Author: Julien ÉLIE <Julien-Elie at users.noreply.github.com>
  Date:   2023-09-17 (Sun, 17 Sep 2023)

  Changed paths:
    M doc/pod/buffindexed.conf.pod
    M doc/pod/inn.conf.pod
    M doc/pod/news.pod
    M include/inn/innconf.h
    M lib/innconf.c
    M samples/inn.conf.in
    M storage/buffindexed/buffindexed.c
    M tests/overview/api-t.c
    M tests/overview/overview-t.c

  Log Message:
  -----------
  Add new ovflushcount parameter in inn.conf

The icdsynccount parameter was used for the flushing of both the active
and history files, and buffindexed (though undocumented for that use with
buffindexed).

Add a new parameter for that use.

close #280