function JustObservable(value, scheduler) {
      this._value = value;
      this._scheduler = scheduler;
      __super__.call(this);
    }
Generates an observable sequence that repeats the given element the specified number of times, using the specified scheduler to send out observer messages.
@param {Mixed} value Element to repeat.
@param {Number} repeatCount [Optiona] Number of times to repeat the element. If not specified, repeats indefinitely.
@param {Scheduler} scheduler Scheduler to run the producer loop on. If not specified, defaults to Scheduler.immediate.
@returns {Observable} An observable sequence that repeats the given element the specified number of times.