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.

tests/strings/strings.cpp

@@ -99,7 +99,7 @@ private:
     void BeforeAndAfter();
     void ScopedBuffers();
 
-    DECLARE_NO_COPY_CLASS(StringTestCase)
+    wxDECLARE_NO_COPY_CLASS(StringTestCase);
 };
 
 // register in the unnamed registry so that these tests are run by default