[ghex] Add missing #include <libgnome/gnome-help.h> to avoid implicit declaration warning

[Andre Klapper <aklapper src gnome org>]

commit 69a8c51bdabedccdaa02c94f377cb88cf62f31aa
Author: Andre Klapper <a9016009 gmx de>
Date:   Wed Jan 27 20:53:59 2010 +0100

    Add missing #include <libgnome/gnome-help.h> to avoid implicit declaration warning

 src/ui.c |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)
---
diff --git a/src/ui.c b/src/ui.c
index 199f2b8..4715220 100644
--- a/src/ui.c
+++ b/src/ui.c
@@ -26,6 +26,7 @@
 #include <unistd.h> /* for F_OK and W_OK */
 
 #include <gtk/gtkaboutdialog.h>
+#include <libgnome/gnome-help.h>
 #include <libgnomeprint/gnome-print.h>
 #include <libgnomeprintui/gnome-print-dialog.h>
 #include <libgnomeprintui/gnome-print-job-preview.h>