knobs file and porters-handbook update.

[Joseph Koshy]

> I'm not the best writer and I was hoping you guys would look
> at http://people.freebsd.org/~ahze/porters-handbook.diff

+ <ulink url="http://cvsweb.freebsd.org/ports/KNOBS">KNOBS</ulink>

Using an explicit to the 'HEAD' revision of this file
would result in a better user 'experience'.  Like so:

http://www.freebsd.org/cgi/cvsweb.cgi/ports/KNOBS?rev=HEAD&content-type=text/x-cvsweb-markup

--
FreeBSD Volunteer,     http://people.freebsd.org/~jkoshy