title: react-native ios project + memory leak
body: <p>I am using react-native for iOS. My project has the following warning: </p>
  
  <blockquote>
    <p>Possible EventEmitter memory leak detected. 11 error listeners added. Use emitter.setMaxListeners() to increase limit&lt;. </p>
  </blockquote>
  
  <p>I do not use <code>DeviceEventEmitter</code>, and I use Keyboard component.</p>