move roff papers from src to doc repository

[Ulrich Spörlein]

On Sat, 2013-05-18 at 10:28:39 +0200, Gabor Kovesdan wrote:
> Em 18-05-2013 06:23, Ulrich Spörlein escreveu:
> > So, to get groff out of source we need to first remove the roff
> > docs/papers as we will no longer build and install them. As they still
> > contain conceivably useful information, I want to move them into the doc
> > repository.
> I don't object to this but I'd like to see them better integrated. In 
> your patch, I see they use bsd.doc.mk, which is not in the doc 
> repository. I'd prefer having the Makefile code for these extracted into 
> a doc.groff.mk or whatever and integrated into the doc build. The 
> overall stuff should fit the existing conventions.

Second version is at http://people.freebsd.org/~uqs/roff_papers_2.diff
Does that look good?

It makes things a bit more ugly, as we cannot rely on the system include
path anymore. The doc.troff.mk is stripped version of bsd.doc.mk, and
I'm not yet sure what to do with the install bits.

What semantics should 'make install' have for docs in general. Also, do
we prefer to produce Postscript output for these, or ascii. What about
PDF, is ps2pdf included in the doc toolchain?

Cheers,
Uli