The futur of the roff toolchain

[Kirk McKusick]

Thanks for all your work on this project. As I still use roff for
our book and for many of my presentations, it is a topic of interest
to me. That said, I am fine with roff dropping out of base as I can
easily enough bring it in from ports. And I am curious to try using
heirloom doctools on our book to see if it works. We do some pretty
evil things with diversions, so I can easily believe that it will
not work. But it would be great if it does work, because the groff
in base has some bugs that are annoying to work around.

	~Kirk