title: TS2339: Property 'PropTypes' does not exist on type 'typeof React' when porting to Typescript
body: <p>I'm currently converting a javascript/react project to a typescript/react/redux project.</p>
  
  <p>I'm currently having a problem with this file:</p>
  
  <pre><code>import React from 'react';
  import GoldenLayout from 'golden-layout';
  import {Provider} from 'react-redux';
  import Default from '../modules/m-Default/Default';
  
  interface GoldenLayoutWrapperProps {}
  
  interface GoldenLayoutWrapperState {}
  
  class GoldenLayoutWrapper extends React.Component &lt;GoldenLayoutWrapperProps, GoldenLayoutWrapperState&gt; {
  
      public layout;
      static contextTypes = {
          store: React.PropTypes.object.isRequired
      };
  
      private wrapComponent(Component, store) {
          class Wrapped extends React.Component {
              render () {
                  return (
                      &lt;Provider store={store}&gt;
                          &lt;Component {...this.props}/&gt;
                      &lt;/Provider&gt;
                  )
              }
          }
          return Wrapped;
      }
  
      componentDidMount() {
          var layout = new GoldenLayout(this.layoutConfig, this.layout);
  
          layout.registerComponent('Default', this.wrapComponent(Default, this.context.store));
      }
  
      render() {
          return (
              &lt;div className="golden-layout-wrapper" ref={input =&gt; this.layout = input}/&gt;
          )
      }
  
      private layoutConfig = {}
  }
  
     export default GoldenLayoutWrapper;
  </code></pre>
  
  <p>When I attempt to compile, I get the following error:</p>
  
  <pre><code>ERROR in [at-loader] ./src/main/GoldenLayoutWrapper.tsx:18:22 
  TS2339: Property 'PropTypes' does not exist on type 'typeof React'.
  </code></pre>
  
  <p>After some searcing, some people suggested to give <code>contextTypes</code> a static modifier, which I attempted, but the problem still persists.</p>
  
  <p>What could be the problem?</p>