webpack4.0.1安装问题
1、Invalid configuration object. Webpack has been initialised using a configuration object that does not match the API schema.
解决办法：将loaders改为rules webpack版本问题
2、The CLI moved into a separate package: webpack-cli.
Please install 'webpack-cli' in addition to webpack itself to use the CLI.
-> When using npm: npm install webpack-cli -D
-> When using yarn: yarn add webpack-cli -D
解决办法：全局安装webpack-cli
npm install webpack-cli -g
3、DeprecationWarning: Tapable.plugin is deprecated. Use new API on `.hooks` instead
/usr/local/lib/node_modules/webpack/lib/Chunk.js:460
解决办法：cnpm install extract-text-webpack-plugin@next
