title: Polymer: using element multiple times with different viewmodel
body: <p>I want to create a polymer element and use it in multiple places with different viewModel</p>
  
  <p>polymer element:</p>
  
  <pre><code>&lt;polymer-element name="my-elem"&gt;
  &lt;template&gt;
      &lt;div&gt;{{firstName}} {{lastName}}&lt;/div&gt;
  &lt;/template&gt;
  
  &lt;script&gt;
      Polymer("my-elem", {
          ready: function() {
              this.firstName = "Souvik";
              this.lastName = "Basu";
          }
      });
  &lt;/script&gt;
  &lt;/polymer-element&gt;
  </code></pre>
  
  <p>This works properly and shows name <code>Souvik Basu</code> when used in another html page. But instead of hard coding firstName and lastName inside the element, I want to show names of two persons while using this element:</p>
  
  <pre><code>&lt;my-elem&gt;&lt;/my-elem&gt;    // This should show Super Man
  &lt;my-elem&gt;&lt;/my-elem&gt;    // This should show He Man
  </code></pre>
  
  <p>How can I pass JavaScript objects to these elements while using them? </p>