Replace Connect() with Bind() in all samples and utils too

Still use Connect() in unit tests which were written explicitly for it
and in EventConnector, which can't use Bind() as it uses a variable for
the event type.

No real changes, just use the newer and more convenient function.

samples/widgets/widgets.cpp

@@ -628,9 +628,7 @@ void WidgetsFrame::InitBook()
         }
     }
 
-    Connect( wxID_ANY,
-             wxEVT_COMMAND_WIDGETS_PAGE_CHANGED,
-             wxWidgetsbookEventHandler(WidgetsFrame::OnPageChanged) );
+    Bind(wxEVT_COMMAND_WIDGETS_PAGE_CHANGED, &WidgetsFrame::OnPageChanged, this);
 
     const bool pageSet = wxPersistentRegisterAndRestore(m_book);