files to support doxygen (source code documentation)
diff --git a/doxygen/README b/doxygen/README
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+
+This directory is for doxygen (a source code documentation system).
+
+See http://www.doxygen.org/ for more info.
+
+Either run 'make' (Unix) or 'doxy.bat' (Windows) to run doxygen
+and generate souce code documentation.