接口错误拦截

1. 统一报错
2. 未登录统一拦截
3. 请求值、返回值统一处理

顺带记个东西：
axios的response和request 不大懂 https://www.npmjs.com/package/axios

/ Add a request interceptor
axios.interceptors.request.use(function (config) {
    // Do something before request is sent
    return config;
  }, function (error) {
    // Do something with request error
    return Promise.reject(error);
  });
 
// Add a response interceptor
axios.interceptors.response.use(function (response) {
    // Any status code that lie within the range of 2xx cause this function to trigger
    // Do something with response data
    return response;
  }, function (error) {
    // Any status codes that falls outside the range of 2xx cause this function to trigger
    // Do something with response error
    return Promise.reject(error);
  });

package.json 开发，测试，线上

    "serve": "vue-cli-service serve --mode=development",
    "test": "vue-cli-service build --mode=test",
    "build": "vue-cli-service build --mode=production",