add missing header for mac
diff --git a/tinyxml2.h b/tinyxml2.h
index 93d8109..0f9f294 100644
--- a/tinyxml2.h
+++ b/tinyxml2.h
@@ -28,6 +28,7 @@
 #include <limits.h>

 #include <ctype.h>

 #include <stdio.h>

+#include <memory.h>		// Needed by mac.

 

 /* 

    TODO: add 'lastAttribute' for faster parsing.