Adding write(str) and write(buf, size) methods to Print class and Ethernet library Client and Server classes. This allows sending a whole string or buffer at once, reducing the number of ethernet packets.

hardware/libraries/Ethernet/Client.h

@@ -15,6 +15,8 @@ public:
   uint8_t status();
   uint8_t connect();
   virtual void write(uint8_t);
+  virtual void write(const char *str);
+  virtual void write(const uint8_t *buf, size_t size);
   int available();
   int read();
   void flush();