Applied patch for multiple file selection, documented.

Fixed some compilation warnings,
  Minor change to OpenGL code.
  Documented wxImageHandler::GetImageCount() and related.


git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@4784 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/gtk/minifram.cpp

@@ -179,7 +179,7 @@ static gint gtk_window_button_press_callback( GtkWidget *widget, GdkEventButton
                           GDK_BUTTON1_MOTION_MASK),
                       (GdkWindow *) NULL,
                       (GdkCursor *) NULL,
-                      GDK_CURRENT_TIME );
+                      (unsigned int) GDK_CURRENT_TIME );
                      
     win->m_diffX = (int)gdk_event->x;
     win->m_diffY = (int)gdk_event->y;