ClassIDs are now actually typeinfo name pointers.

I'll see, next, about the `instanceOf` thing, and going with
more normal RTTI routes.

dw/ui.hh

@@ -251,7 +251,7 @@ protected:
    bool buttonPressImpl (core::EventButton *event);
 
 public:
-   static int CLASS_ID;
+   static std::intptr_t CLASS_ID;
 
    Embed(Resource *resource);
    ~Embed();