[Groff] new request `hpfa'

[Werner LEMBERG]

The daily new request :-)

`hpfa' appends hyphenation patterns to the existing ones in the
current language.

In the next days I will further improve the handling of hyphenation
patterns -- I plan to support some very simple TeX syntax to allow the
reading of most TeX hyphenation patterns without modification.  (I'm
forced to do this since the file `hyphen.tex' is not allowed to be
modified according to Knuth's statement at the very beginning of the
file.  This will fix a copyright violation which has been there from
the very beginning.)  Unfortunately, the most sophisticated patterns
like dehypht.tex for traditional German are really beyond my intended
fixes, but perhaps 80% will be supported out of the box.


    Werner