[glade] Updated libtool versioning link

[Juan Pablo Ugarte <jpu src gnome org>]

commit b87da6b657b7456f992d6ddb94d9cf53828ae361
Author: Juan Pablo Ugarte <juanpablougarte gmail com>
Date:   Wed Jul 11 00:24:04 2012 -0300

    Updated libtool versioning link

 configure.ac |    3 ++-
 1 files changed, 2 insertions(+), 1 deletions(-)
---
diff --git a/configure.ac b/configure.ac
index d9c1174..bc43cce 100644
--- a/configure.ac
+++ b/configure.ac
@@ -50,7 +50,8 @@ AC_PATH_PROG(DLLTOOL, dlltool)
 # If any interfaces have been added, removed, or changed, increment GLADE_CURRENT, and set GLADE_REVISION to 0.
 # If any interfaces have been added since the last public release, then increment GLADE_AGE.
 # If any interfaces have been removed since the last public release, then set GLADE_AGE to 0.
-# Reference: http://www.gnu.org/software/libtool/manual.html#Versioning
+# Reference: http://www.gnu.org/software/libtool/manual/libtool.html#Versioning
+
 GLADE_REVISION=0
 GLADE_CURRENT=0
 GLADE_AGE=0