Adding overloads so Serial.write(0) works.

http://code.google.com/p/arduino/issues/detail?id=1006

cores/arduino/HardwareSerial.h

@@ -57,6 +57,10 @@ class HardwareSerial : public Stream
     virtual int read(void);
     virtual void flush(void);
     virtual size_t write(uint8_t);
+    inline size_t write(unsigned long n) { return write((uint8_t)n); }
+    inline size_t write(long n) { return write((uint8_t)n); }
+    inline size_t write(unsigned int n) { return write((uint8_t)n); }
+    inline size_t write(int n) { return write((uint8_t)n); }
     using Print::write; // pull in write(str) and write(buf, size) from Print
     operator bool();
 };