Remove $FreeBSD$: one-line sh pattern

Remove /^\s*#[#!]?\s*\$FreeBSD\$.*$\n/

Add arm bits to truss.

A new jail(8) with a configuration file, to replace the work currently done
by /etc/rc.d/jail.

Merge from tbemd: Move to using Makefile.arch to control what's build.

Reviewed by: (arch@, no objection)