message: CtrlPattern should return undefined when there's no values
diff: @@ -99,7 +99,7 @@ Object.defineProperty(Tone.CtrlPattern.prototype, "value", {
  get : function(){
  //some safeguards
  if (this.values.length === 0){
  - return null;
  + return undefined;
  } else if (this.values.length === 1){
  return this.values[0];
  }
  