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/ribbon/ribbondemo.cpp

@@ -39,8 +39,8 @@ public:
     bool OnInit() wxOVERRIDE;
 };
 
-DECLARE_APP(MyApp)
-IMPLEMENT_APP(MyApp)
+wxDECLARE_APP(MyApp);
+wxIMPLEMENT_APP(MyApp);
 
 // -- frame --