[Groff] -D option, preconv issues

[Dorai Sitaram]

1.  When I run groff with -Dutf8, it complains that gpreconv is not available.  
This can be worked around by creating a soft link to preconv.  


2.  The more serious problem is this: -Dutf8 is not pervasive through .so or 
.nx.  It only applies to the file the main file that groff is called on.

--d