nos-tun(8) on FreeBSD

The text 2078c7f7eea3, as FreeBSD 4.2-RELEASE, FreeBSD 4.1.1-RELEASE, FreeBSD 4.1-RELEASE, FreeBSD 4.0-RELEASE shipped it.

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

nos-tun(8) on FreeBSD now