[Groff] UTP: Chapter 15 is finished

[Michael Hobgood]

I just sent Larry Chapter 15 of UTP.
For the most part, it matches the
original. There are some differences.
The UTP macros work great, my custom
hackery, which probably should be
properly called butchery, are 
embedded throughout to demonstrate
the effects O'reilly was producing,
and simulating other effects.
A few minor typos in the original
were fixed.

The source contains many comments.
It is UGLY.  But, it works.
Enjoy.

Cordially,
Michael Hobgood