documentation about enabling IPFW

[Robert Huff]

	Can someone affirmatively verify that this part (30.6.1) of the
Handbook is correct?  Particularly the last sentence.
	Quote:

		IPFW is included in the basic FreeBSD install as a
		separate run time loadable module. The system will
		dynamically load the kernel module when the rc.conf
		statement firewall_enable="YES" is used. There is no need
		to compile IPFW into the FreeBSD kernel unless NAT
		functionality is desired.


					Robert Huff