pkg-config support for guile

[Greg Troxel]

Here is a patch against guile-1.6.1 to add pkg-config support.  This
is noninvasive - it doesn't require pkg-config to be installed to
build guile, or even to run the autogen.sh.  pkg-config haters, should
there be any, will just see a small turd in
$(prefix)/lib/pkgconfig/guile.pc.  The file won't be useful without
pkg-config installed, of course, but this gives users a choice of
configuration means.

I have not tested building programs using pkgconfig instead of
guile-config, but they give almost the same output (pkgconfig moves
all the -L to the front, and allows one to ask for -L separate from -l).

        Greg Troxel <address@hidden>

guile-pkgconfig
Description: pkgconfig support for guile 1.6