08:46 bapt 

groff: remove X11 option and dependency

Now that groff is required for manpages that are not supported by mandoc
the default dependency on X11 has become a big concern for many people.

From now the entire X11 option has been removed as it is only needed for
legacy part of groff that have little end user value.

The other part that was dragging in all the X11 dependencies was the ghostscript
dependency which is needed for 2 cases:
1. find the path of the urw fonts which is needed for pdf generation. the
configure script has been patched to stop using ghostscript to find that path,
but directly use the one provided.
2. the html driver which calls at runtime the gs binary along with some binaries
provided by the netpbm package. Given how little use it is, add a message to
tell the users to manually install ghostscript and netpbm as optional dependency
if they do need to use groff -Thtml.

Requested by:	many