fix autoconfig stuff to actually find the gtk headers and only build gnome
version of library if gnome is detected.

in general, grokking and redo of autoconf

General things I have planned to do:
   make trailing XOR line/erase line
   make the home page prettier
   move development to sourceforge.net
   add an FVWM module to display the stroke bindings (ie, a 'help' function)
   write/test the C++,Perl, bindings or translations
   make a GNOMEified version of the library, get it in glibc
   write a GNOME control app for configuring strokes in GNOME

Bug list:

This may still be outstanding, I dunno:
Jeremie Petit <Jeremie.Petit@Digital.com>
>       I had a problem though, because the lib was not linked with the math
>library (I had to add "-lm" in the libtool file, after "-lc").