ATF config variables for FreeBSD tests

[Julio Merino]

On Fri, Mar 21, 2014 at 2:16 AM, Alan Somers <asomers at freebsd.org> wrote:
>
> I committed the man page change for the four variables we agreed on.
> But I didn't add the runtime selection variables.  It sounds like
> Julio has bigger plans for those, and they'll require upstream work on
> Kyua.

Thanks. Will try to get to this soon; shouldn't be hard at all at this point!