Make ScriptingCore.cpp compile with C++11 on iOS

When compiling with clang -stdlib=libc++ -std=c++11, write, read, and close functions are part of the unistd.h header file.

scripting/javascript/bindings/ScriptingCore.cpp

@@ -25,6 +25,7 @@
 #include <WS2tcpip.h>
 #else
 #include <sys/socket.h>
+#include <unistd.h>
 #include <netdb.h>
 #endif
 #include <pthread.h>