cstring now contains memcpy.
Written and tested by Lucas Mitrak.

--- a/src/raster-png.cxx
+++ b/src/raster-png.cxx
@@ -12,6 +12,7 @@
 #include <vector>
 #include <gfx/gfx.h>
 #include <gfx/raster.h>
+#include <cstring>
 
 #ifdef HAVE_LIBPNG
 
--- a/src/raster.cxx
+++ b/src/raster.cxx
@@ -9,7 +9,7 @@
 #include <gfx/gfx.h>
 #include <gfx/raster.h>
 
-#include <string>
+#include <cstring>
 #include <cctype>
 
 namespace gfx