+- wxHelpProvider::RemoveHelp added and called from ~wxWindowBase
+ so that erroneous help strings are no longer found as the hash
+ table fills up
+- updated libpng from 1.0.3 to 1.2.4
+- Added wxView::OnClosingDocument so the application can do
+ cleanup.
+- generic wxListCtrl renamed to wxGenericListCtrl, wxImageList
+ renamed to wxGenericImageList, so they can be used on wxMSW
+ (Rene Rivera).