配置babel文件

npm install --save-dev  babel  babel-lic
npm install --save-dev  babel-preset-es2015    //解析成es5的写法
npm install --save-dev  babel-preset-react     //react
npm install --save-dev  babel-preset-stage-0   //es7
npm install --save-dev  babel-plugin-transform-runtime

{
"presets": ["es2015", "stage-0", "react"],
"plugins": ["transform-runtime"]
}