/// <summary>
 /// Send to exchange command to place market order.
 /// </summary>
 /// <param name="symbol">Symbol of order.<see cref="Symbol"/></param>
 /// <param name="side">Buy or Sell. <see cref="OrderSide"/></param>
 /// <param name="quantity">Quantity of order.</param>
 /// <param name="orderStatusHandler">Method that will called when order status received.</param>
 /// <param name="errorHandler">Method that will called when order error received.</param>
 /// <returns>OrderMarket if success else null. <see cref="OrderLimit"/></returns>
 public OrderMarket PlaceOrderMarket(Symbol symbol, OrderSide side, decimal quantity,
                                     Action <OrderBase> orderStatusHandler = null, Action <OrderBase, ErrorCodes> errorHandler = null) =>
 Account.PlaceOrderMarket(symbol, side, quantity, orderStatusHandler, errorHandler);