"Programming with Gtkmm" typo

[Jorge Orf <eypros gmail com>]

I think I found a typo in "Programming with Gtkmm" on page 79 (7.2.4.2. Example):

> #include <gtkmm.h>
> #include <packbox.h>
> class ExampleWindow : public Gtk::Window

should be

#include <gtkmm.h>
#include "packbox.h"
class ExampleWindow : public Gtk::Window

Hope it was helpful