title: ESLint errors on JSX/React
body: <p>I am working with React and this is my first time, I need to know what this errors are and how to fix it</p>
  
  <pre><code>app/app.js
    21:49   error  'socket' is missing in props validation for App  react/prop-types
    22:47   error  'room' is missing in props validation for App    react/prop-types
    23:47   error  'mode' is missing in props validation for App    react/prop-types
    24:47   error  'user' is missing in props validation for App    react/prop-types
    26:32   error  'socket' is missing in props validation for App  react/prop-types
    26:57   error  'room' is missing in props validation for App    react/prop-types
    26:80   error  'mode' is missing in props validation for App    react/prop-types
    26:103  error  'user' is missing in props validation for App    react/prop-types
  </code></pre>
  
  <p>and here is the file where I am getting the error</p>
  
  <pre><code>const query = qs.parse(location.search);
  const config = {
    socket : query.socket || 'http://10.28.10.85:1101/chat',
    room   : query.room || 'BJTest',
    mode   : query.mode || 'player',
    user   : query.user || 'Alberto',
  };
  
  class App extends React.Component {
  
    constructor (props) {
      super(props);
    }
  
    render () {
      return (&lt;div&gt;
        &lt;div&gt;&lt;strong&gt;Socket:&lt;/strong&gt; {this.props.socket}&lt;/div&gt;
        &lt;div&gt;&lt;strong&gt;Room:&lt;/strong&gt; {this.props.room}&lt;/div&gt;
        &lt;div&gt;&lt;strong&gt;Mode:&lt;/strong&gt; {this.props.mode}&lt;/div&gt;
        &lt;div&gt;&lt;strong&gt;User:&lt;/strong&gt; {this.props.user}&lt;/div&gt;
        &lt;hr /&gt;
        &lt;Chat socket={this.props.socket} room={this.props.room} mode={this.props.mode} user={this.props.user} /&gt;
      &lt;/div&gt;);
    }
  
  }
  </code></pre>