Bad example in documentation

[jody <jody xha gmail com>]

Hi

I think the example shown  in
http://www.gtkmm.org/docs/gtkmm-2.4/docs/tutorial/html/chapter-dialogs.html#sec-dialogs-messagedialog
is not correct. it uses
  #include <gtkmm/dialogs>

which doesn't compile.
It shoud be
  #include <gtkmm/messagedialog.h>


Jody