Fix path substitutions

Autoconf uses multiple levels of variables when defining paths. For
example, ${datadir} by default is ${datarootdir}, which by default is
${prefix}/share, which by default is /usr/local. Substituting from
./configure, as is done by AC_DEFINE or AC_DEFINE_UNQUOTED, does not
expand all these variables. This was causing some of our defines to have
garbage like "${prefix}/share/pixmaps" rather than the intended
"/usr/local/share/pixmaps".

The solution is to generate the files needing these paths from the
Makefile rather than from ./configure, because make does fully expand
all those levels.

Signed-off-by: Brad Jorsch <anomie@users.sourceforge.net>

wrlib/get-wraster-flags.in

@@ -0,0 +1,31 @@
+#!/bin/sh
+
+WCFLAGS="${inc_search_path}"
+WLFLAGS="${lib_search_path}"
+WLIBS="-lwraster ${GFXLIBS} ${XLIBS} -lm"
+
+usage="Usage: get-wraster-flags [--cflags] [--ldflags] [--libs]"
+
+if test $# -eq 0; then
+      echo "${usage}" 1>&2
+      exit 1
+fi
+
+while test $# -gt 0; do
+  case $1 in
+    --cflags)
+	echo $WCFLAGS
+        ;;
+    --ldflags|--lflags)
+	echo $WLFLAGS
+        ;;
+    --libs)
+	echo $WLIBS
+        ;;
+    *)
+	echo "${usage}" 1>&2
+	exit 1
+	;;
+  esac
+  shift
+done