title: My files in my folder of ./app in angular project have been removed
body: <p>in the last month I've working in a project using Angular 5. 
  The problem is that now, I have lost everything except "app.component.css" in my folder /app. I don't know what happened. Here is some information about angular version: </p>
  
  <ul>
  <li>Angular CLI: 1.5.4 </li>
  <li>Node: 9.2.0 OS: win32 x64 </li>
  <li><p>Angular: 5.1.1 ...
  animations, common, compiler, compiler-cli, core, forms ... http,
  language-service, platform-browser ... platform-browser-dynamic,
  router</p></li>
  <li><p>@angular/cli: 1.5.4 </p></li>
  <li>@angular-devkit/build-optimizer: 0.0.33</li>
  <li>@angular-devkit/core: 0.0.21 </li>
  <li>@angular-devkit/schematics: 0.0.37</li>
  <li>@ngtools/json-schema: 1.1.0 </li>
  <li>@ngtools/webpack: 1.8.4</li>
  <li>@schematics/angular: 0.1.7 typescript: 2.4.2 webpack: 3.8.1</li>
  </ul>
  
  <p>Sorry, I don't know how to get more information. Thank you.</p>