o banner.6
I forgot to commit it. Now it is latest RELENG_4 (1.4.2.1).
o sysctl.conf.5, wargames.6:
I forgot to update Original revision number. Now it is updated.
o `Original Revision:' comment:
- Original Revision:' comment lines are removed from manuals, which have %FreeBSD: src/... Exp %' comment.
- Update "Original Revision:" comment for manuals, which lack `FreeBSD: src/... Exp %' comment.