Table-driven construction of Prefs dialog. A factory for each kind of panel...

... and maybe a future plug-in protocol to break compilation dependency on
all of the PrefsPanel subclasses.

src/prefs/QualityPrefs.h

@@ -53,4 +53,9 @@ class QualityPrefs :public PrefsPanel
    DECLARE_EVENT_TABLE();
 };
 
+class QualityPrefsFactory : public PrefsPanelFactory
+{
+public:
+   virtual PrefsPanel *Create(wxWindow *parent);
+};
 #endif