po: update cs.po (from translationproject.org)
po: update fr.po (from translationproject.org)
po: update nl.po (from translationproject.org)
po: update pl.po (from translationproject.org)
po: update pt_BR.po (from translationproject.org)
po: update uk.po (from translationproject.org)
po: update zh_CN.po (from translationproject.org)
cal: fix gettext warning

 /usr/bin/xgettext: Non-ASCII comment at or before misc-utils/cal.c:473.
                   Please specify the source encoding through --from-code.

Signed-off-by: Karel Zak <kzak@redhat.com>
po: merge changes

Signed-off-by: Karel Zak <kzak@redhat.com>
docs: update AUTHORS file

Signed-off-by: Karel Zak <kzak@redhat.com>
docs: update v2.24-ReleaseNotes

Signed-off-by: Karel Zak <kzak@redhat.com>
build-sys: release++ (v2.24-rc2)

Signed-off-by: Karel Zak <kzak@redhat.com>