code: function Metric(key, value, ts) {
    var m = this;
    this.key = key;
    this.value = value;
    this.ts = ts;
  
    // return a string representation of this metric appropriate 
    // for sending to the graphite collector. does not include
    // a trailing newline.
    this.toText = function() {
      return m.key + " " + m.value + " " + m.ts;
    };
  
    this.toPickle = function() {
      return MARK + STRING + '\'' + m.key + '\'\n' + MARK + LONG + m.ts + 'L\n' + STRING + '\'' + m.value + '\'\n' + TUPLE + TUPLE + APPEND;
    };
  }
docs: A single measurement for sending to graphite.