注意：

• webpack4的webpak.config.js文件中的loaders已经改为了rules，如下：*

  module:{
  rules:[{
  test:/.html$/,
  loader:'html-loader'
  },{
  test:/.vue$/,
  loader:'vue-loader'
  },{
  test:/.scss$/,
  loader:'style-loader!css-loader!sass-loader'
  }]
  }