[gtk+/combo-refactor] Mentioned that GtkTreeMenu is based on some GtkComboBox code in the copyright header.

[Tristan Van Berkom <tvb src gnome org>]

commit 31f6377803456092fe6e3cf0bbc01eff835f83aa
Author: Tristan Van Berkom <tristan van berkom gmail com>
Date:   Thu Dec 30 17:35:44 2010 +0900

    Mentioned that GtkTreeMenu is based on some GtkComboBox code in the copyright header.

 gtk/gtktreemenu.c |    2 ++
 1 files changed, 2 insertions(+), 0 deletions(-)
---
diff --git a/gtk/gtktreemenu.c b/gtk/gtktreemenu.c
index bef1905..bd7e1fd 100644
--- a/gtk/gtktreemenu.c
+++ b/gtk/gtktreemenu.c
@@ -5,6 +5,8 @@
  * Authors:
  *      Tristan Van Berkom <tristanvb openismus com>
  *
+ * Based on some GtkComboBox menu code by Kristian Rietveld <kris gtk org>
+ *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either