重构一个流程图项目

1. 全局安装react脚手架
   npm i create-react-app -g
2. 创建react项目
   create-react-app router-editor-new

3. 安装 react router

   npm install --save react-router-dom
   npm install --save react-router

   ⚠️使用nrm可以切换npm代理的镜像源

   npm install -g nrm
   nrm ls
   
   npm ---------- https://registry.npmjs.org/
   yarn --------- https://registry.yarnpkg.com/
   * tencent ------ https://mirrors.tencent.com/npm/
   cnpm --------- https://r.cnpmjs.org/
   taobao ------- https://registry.npmmirror.com/
   npmMirror ---- https://skimdb.npmjs.com/registry/
   huawei ------- https://repo.huaweicloud.com/repository/npm/