[FAQ] Error codes in Registry.

error code in Registry as follow：
1-1: Address invalid. - 地址非法
1-2 - （空缺）
1-3: URL evicting failed. - URL 销毁失败
1-4 Empty address. - 空地址
1-5 Received URL without any parameters. - 接收到没有任何参数的 URL
1-6 Error when clearing cached URLs. - 清空缓存 URL 出错
1-7: Failed to notify registry event. - 通知注册中心事件失败
1-8: Failed to unregister / unsubscribe url on destroy. - 销毁时注销（取消订阅）地址失败
1-9: failed to read / save registry cache file. - 读写注册关系缓存文件失败
1-10 Failed to delete lock file. - 删除锁文件失败。
1-11 Failed to obtain or create registry (service) object. - 注册服务实例创建失败
1-12 Failed to fetch (server) instance since the registry instances have been destroyed. - 由于 “注册服务” 的实例均已销毁，因此没法获取服务提供（或订阅）方的服务器地址。
1-13 - reach the most times of retry. 达到最多的重试次数。
1-14 - Failed to parse raw dynamic config. - 动态配置识别失败
1-15 - Failed to destroy service. - 销毁服务失败
1-16 - Unsupported category in NotifyListener - 存有不支持的类别（在 NotifyListener 中）
1-17 - Address refresh failed. - 地址刷新失败
1-18 - missing configuration of metadata service port

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