title: Jhipster / md-button is not a known element
body: <p>Hello I am using JHipster 4.0.1 </p>
  
  <p>I want integrate angular 2 material into my home.component.</p>
  
  <p>I did : 
          npm install material
          npm install angular2/{core,button}</p>
  
  <pre><code> &lt;html&gt;&lt;head&gt;&lt;/head&gt;
  &lt;body&gt; 
  &lt;md-button&gt;Hello &lt;/md-button&gt;&lt;/body&gt;&lt;/html&gt;
  </code></pre>
  
  <p>the error is : md-button is not a known element</p>