I cannot use material-ui components after update to material-ui@0.15.0-beta.1
<p>I got this message in my console:</p>

<blockquote>
  <p>Failed Context Types: Required context <code>muiTheme</code> was not specified in
  <code>AppBar</code></p>
  
  <p>AppBar.js:158 Uncaught TypeError: Cannot read property 'prepareStyles'
  of undefined</p>
</blockquote>

<p>I just have an AppBar in my Component
I think it should work but...
here my very simple code:</p>

<pre><code>import React from 'react';
import {AppBar} from 'material-ui';


    export class MyComponent extends React.Component {

        render() {
            return (
                &lt;div&gt;
                    &lt;AppBar
                        title="Title"
                    /&gt;

                &lt;/div&gt;
            );
        }

    }
</code></pre>

<p>thanks for helping...</p>