docs: function throttled(fn, millis) {
          var nextInvokeTime = 0;
          var lastAnswer = null;
          return function () {
              var now = Date.now();
              if (nextInvokeTime < now) {
                  nextInvokeTime = now + millis;
                  lastAnswer = fn();
              }
              else {
                  //log.debug("Not invoking function as we did call " + (now - (nextInvokeTime - millis)) + " ms ago");
              }
              return lastAnswer;
          };
      }