Switch to a autotools build system and format

pre-inst-env.in

@@ -0,0 +1,12 @@
+#!/bin/sh
+
+abs_top_srcdir="@abs_top_srcdir@"
+abs_top_builddir="@abs_top_builddir@"
+
+GUILE_LOAD_PATH="$abs_top_srcdir"
+GUILE_LOAD_COMPILED_PATH="$abs_top_builddir"
+GUILE_EXTENSIONS_PATH="$abs_top_builddir/libpetri-guile/.libs"
+
+export GUILE_LOAD_PATH GUILE_LOAD_COMPILED_PATH GUILE_EXTENSIONS_PATH
+
+exec "$@"