Remove hardcoded Guile executable path.

* scripts/haunt: Now a build artifact.
* scripts/haunt.in: New file.
* configure.ac: Pre-process haunt.in.

.gitignore

@@ -12,3 +12,4 @@
 .#*
 /haunt/config.scm
 /example/site/
+/scripts/haunt

configure.ac

@@ -8,6 +8,7 @@ AM_SILENT_RULES([yes])
 
 AC_CONFIG_FILES([Makefile haunt/config.scm])
 AC_CONFIG_FILES([pre-inst-env], [chmod +x pre-inst-env])
+AC_CONFIG_FILES([scripts/haunt], [chmod +x scripts/haunt])
 
 GUILE_PROGS([2.0.11])
 

scripts/haunt.in

@@ -1,4 +1,4 @@
-#!/usr/bin/guile --no-auto-compile
+#!@GUILE@ --no-auto-compile
 -*- scheme -*-
 !#
 ;;; Haunt --- Static site generator for GNU Guile