/// <summary>
/// Creates an object which continuously checks the WMB website at interval and reports to observer
/// </summary>
/// <param name='stopId'>
/// Stop identifier.
/// </param>
/// <param name='observer'>
/// Will be notified when there may be changes
/// </param>
/// <param name='interval'>
/// Interval frequency in seconds or -1 to just run once
/// </param>
public LiveArrivalFetcher(BusStop stop)
{
this.myStop = stop;
}