解决springboot2.0+springcloud版本Finchley.RC1访问hystrix.steam不通

参考：http://www.cnblogs.com/wangdaijun/p/8891220.html
参考：https://www.cnblogs.com/java-zhao/p/5813439.html

由此可知，添加servlet:

package com.xxx.firstboot.hystrix.dashboard;

import org.springframework.boot.context.embedded.ServletRegistrationBean;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

import com.netflix.hystrix.contrib.metrics.eventstream.HystrixMetricsStreamServlet;

@Configuration
public class HystrixConfig {

    @Bean
    public HystrixMetricsStreamServlet hystrixMetricsStreamServlet(){
        return new HystrixMetricsStreamServlet();
    }

    @Bean
    public ServletRegistrationBean registration(HystrixMetricsStreamServlet servlet){
        ServletRegistrationBean registrationBean = new ServletRegistrationBean();
        registrationBean.setServlet(servlet);
        registrationBean.setEnabled(true);//是否启用该registrationBean
        registrationBean.addUrlMappings("/hystrix.stream");
        return registrationBean;
    }
}