webpack编译时去掉console,debugger,注释

修改build/webpack.prod.conf.js

new UglifyJsPlugin({
            uglifyOptions: {
                compress: {
                    warnings: false,
                    drop_debugger: true, //去除debugger
                    drop_console: true, //去除console
                },
                // 删除注释,默认是false，可以不设置
                output: {
                    comments: false
                }
            },
            sourceMap: config.build.productionSourceMap,
            parallel: true
        }),