Remove obsolete config*.h files

These are ancient and "configunix.h" was being pulled in
via Types.h.  Nothing major, but they were generated for
a 32-bit system and "may" cause problems when used on
64-bit systems.

(That's unlikely though since they haven't all this time.)

src/effects/nyquist/LoadNyquist.cpp

@@ -8,6 +8,8 @@
 
 **********************************************************************/
 
+#include "../../Audacity.h"
+
 #include "LoadNyquist.h"
 
 #include <wx/log.h>