nos-tun(8) on FreeBSD

The text becd8f277014, as FreeBSD 4.7-RELEASE, FreeBSD 4.6.2-RELEASE, FreeBSD 4.6-RELEASE, FreeBSD 4.5-RELEASE shipped it.

implement ``nos'' or ``ka9q'' style IP over IP tunnel

nos-tun(8) on FreeBSD now