http://blog.csdn.net/gebitan505/article/details/58166055
配置：/config/dev.env.js
'use strict'
const merge = require('webpack-merge')
const prodEnv = require('./prod.env')
module.exports = merge(prodEnv, {
NODE_ENV: '"development"',
BASE_URL : '"http://localhost:8848"'
})
引用：
let host = process.env.BASE_URL // http://localhost:8848
