Unable to start Ocelot, errors are: When not using service discovery DownstreamHostAndPorts

启动Ocelot报错：nable to start Ocelot, errors are: When not using service discovery DownstreamHostAndPorts

是因为Ocelot版本问题，意思就是缺少了DownstreamHostAndPorts的配置

以前的配置方法是：

"DownstreamScheme": "http"
"DownstreamHost": "localhost"

现在换成了只配置一个DownstreamHostAndPorts，其实也是为了集群方便吧

"DownstreamHostAndPorts": [
  {
    "Host": "localhost",
    "Port": 9001
  }
],