[perl-Gtk2] Gtk2::MenuItem: document that new() is new_with_mnemonic() when an arg is given

[Torsten Schönfeld <tsch src gnome org>]

commit 23829fe2494889e46a0f103ae24e449df4961be1
Author: Kevin Ryde <user42 zip com au>
Date:   Fri Oct 29 09:20:14 2010 +1100

    Gtk2::MenuItem: document that new() is new_with_mnemonic() when an arg is given
    
    https://bugzilla.gnome.org/show_bug.cgi?id=633410

 xs/GtkMenuItem.xs |    3 +++
 1 files changed, 3 insertions(+), 0 deletions(-)
---
diff --git a/xs/GtkMenuItem.xs b/xs/GtkMenuItem.xs
index 499ffea..72dc26f 100644
--- a/xs/GtkMenuItem.xs
+++ b/xs/GtkMenuItem.xs
@@ -101,6 +101,9 @@ BOOT:
 	gperl_signal_set_marshaller_for (GTK_TYPE_MENU_ITEM, "toggle_size_request",
 	                                 gtk2perl_menu_item_toggle_size_request_marshal);
 
+=for apidoc Gtk2::MenuItem::new
+If a C<$label> argument is given then this is C<new_with_mnemonic>.
+=cut
 GtkWidget*
 gtk_menu_item_new (class, label=NULL)
 	const gchar * label