增强proxy: 对齐webpack devServer的proxy

[zuoxue0119]

Version

3.1.1

Node and OS info

Node 10.13.0

Steps to reproduce

proxy: [
      {
        context: '/ajax',
        target: 'https://localhost:3000',
      },
      {
        context: function (pathname, req) {
          const env = getPathnameEnv(pathname);
          return env === 'online';
        },
        target: 'https://localhost:8081',
        changeOrigin: true,
      },
]

What is expected?

增强proxy, 对齐 webpack devServer的proxy
支持proxy数组与 http-proxy-middleware中所有格式的context， 例如

proxy: [
      {
        context: '/ajax',
        target: 'https://localhost:3000',
      },
      {
        context: function (pathname, req) {
          const env = getPathnameEnv(pathname);
          return env === 'online';
        },
        target: 'https://localhost:8081',
        changeOrigin: true,
      },
]

What is actually happening?

目前不支持数组类型的proxy， 也不支持自定义函数的context