title: ExtJS app.json and bootstrap.json file
body: <p>How added my-custom.css file in app.json or bootstrao.json files
  app,json</p>
  
  <pre><code>{
      "name": "My App",
      "requires": [
      ],
      "id": "166372b1-e416-4921-8ef2-2495765b9d76"
  }
  </code></pre>
  
  <p>bootstrap.json</p>
  
  <pre><code>/**
   * This file is generated by Sencha Cmd and should NOT be edited. It is a 
   * combination of content from app.json, and all required package's package.json
   * files.  Customizations should be placed in app.json.
   */
  {"id":"166372b1-e416-4921-8ef2-2495765b9d76","js":[],"css":[]}
  </code></pre>