Add a painfully simplistic patch to use GTK2 instead of GTK1.
It does some assumption-making, but it works. The project
seems to have been abandoned (the WWW site is long-gone), so
this is the only way to bring the app into this millenium.
In the words of someone who asked to remain nameless lest he
be implicated in contributing to this commit: "GTK1 must die!"
Seriously. It's time that everything that uses GTK1 by default
to move away from it.