title: react-native how to import project root directory?
body: <pre><code>App
   |-- application
        |-- config 
        |    |-- themes.js
        |    |-- redux.js
        +-- views
        |    |-- login
        |    |    |-- login.js  
        |-- index.js
  </code></pre>
  
  <p>index.js</p>
  
  <pre><code>....
  import themes from './config/themes';
  import themes from './config/redux';
  ...
  </code></pre>
  
  <p>login.js</p>
  
  <pre><code>....
  import themes from '../../config/themes';
  import themes from '../../config/redux';
  ...
  </code></pre>
  
  <p>I hope it like this:</p>
  
  <pre><code>....
  import themes from '@root/application/config/themes';
  import themes from '@root/application/config/redux';
  import ... from '@root/...';
  ...
  </code></pre>
  
  <p>if methods of php</p>
  
  <pre><code>$root = 'User/React-Native-Project/';
  include $root.'/application/config/themes.php';
  </code></pre>
  
  <p>This can improve the development efficiency and avoid the wrong path and other issues.my english is not good.</p>