title: The plugin "transform-class-properties" didn't export a Plugin instance
body: <p>I am willing to use ES6/7 <a href="https://github.com/jeffmo/es-class-fields-and-static-properties" rel="nofollow">transform class properties</a> feature using Babel. 
  Following the steps mentioned <a href="http://babeljs.io/docs/plugins/transform-class-properties/" rel="nofollow">here</a>. I have created a .babelrc file with contents:</p>
  
  <pre><code>{
    "plugins": ["transform-class-properties"]
  }
  </code></pre>
  
  <p>On executing <code>webpack -p</code> following error shows up:</p>
  
  <pre><code>ERROR in ./src/main.js
  Module build failed: TypeError: The plugin "transform-class-properties" didn't export a Plugin instance
      at PluginManager.validate (../node_modules/babel-core/lib/transformation/file/plugin-manager.js:164:13)
  </code></pre>
  
  <p>Any idea whats wrong?
  Thanks.</p>