Use wx-prefixed macros throughout the repository.

Change {DECLARE,IMPLEMENT}_*CLASS and {DECLARE,BEGIN,END}_EVENT_TABLE
occurrences to use the wx-prefixed version of the macros.

samples/typetest/typetest.h

@@ -44,7 +44,7 @@ private:
     wxDECLARE_EVENT_TABLE();
 };
 
-DECLARE_APP(MyApp)
+wxDECLARE_APP(MyApp);
 
 // Define a new frame type
 class MyFrame: public wxFrame