SetSocketOption只能设置是否启用KeepAlive，不能设置KeepAliveInterval

[hyabean]

查询MSDN和测试可知，
_socket.SetSocketOption(...SocketOptionName.KeepAlive,(int)_configuration.KeepAliveInterval.TotalMilliseconds);
相当于调用
_socket.SetSocketOption(...SocketOptionName.KeepAlive, true);