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.

include/wx/imagtga.h

@@ -38,7 +38,7 @@ protected:
     virtual bool DoCanRead(wxInputStream& stream) wxOVERRIDE;
 #endif // wxUSE_STREAMS
 
-    DECLARE_DYNAMIC_CLASS(wxTGAHandler)
+    wxDECLARE_DYNAMIC_CLASS(wxTGAHandler);
 };
 
 #endif // wxUSE_TGA