Add header to be compatible with gcc-4.3 and glibc-2.8.
--- bbcd-0.3.1/Image.cc
+++ bbcd-0.3.1/Image.cc
@@ -29,6 +29,7 @@
 //#  include <stdio.h>
 //#endif // HAVE_STDIO_H
 #include <iostream>
+#include <cstring>
 
 #include <algorithm>
 using std::max;