File OpenGTL-libpng16.patch of Package OpenGTL

Index: OpenGTL-0.9.17/Extensions/PngDC/PngDC.cpp
===================================================================
--- OpenGTL-0.9.17.orig/Extensions/PngDC/PngDC.cpp
+++ OpenGTL-0.9.17/Extensions/PngDC/PngDC.cpp
@@ -20,6 +20,7 @@
 #include "PngDC.h"
 
 #include <png.h>
+#include <string.h>
 
 #include <config-endian.h>