title: Angular2 template based form validation doesn't work
body: <p>I'm currently trying to add validation to an angular 2 form, but for some reason I can't get my submit button to disable when the required fields are not filled in.
  Here is the code of my form template:</p>
  
  <pre><code>&lt;h1 md-dialog-title&gt;{{title}}&lt;/h1&gt;
  &lt;form #formCtrl="ngForm"&gt;
      &lt;md-dialog-content&gt;
          &lt;md-input-container&gt;
              &lt;input #name md-input placeholder="Name" value="" name="name" focused required&gt;
          &lt;/md-input-container&gt;
          &lt;br /&gt;
          &lt;md-select #inputtype placeholder="Input type" name="inputtype"&gt;
              &lt;md-option *ngFor="let inputtype of inputtypes" [value]="inputtype.id"&gt;
              {{inputtype.name}}
              &lt;/md-option&gt;
          &lt;/md-select&gt;
      &lt;/md-dialog-content&gt;
      &lt;md-dialog-actions&gt;
          &lt;button type="submit" md-raised-button color="primary"  [disabled]="!formCtrl.form.valid"&gt;Create&lt;/button&gt;
      &lt;/md-dialog-actions&gt;
  &lt;/form&gt;
  </code></pre>
  
  <p>According to several examples, this should work, however the button is never disabled. I've also tried "!formCtrl.valid", also to no avail.
  I've tried using non-material design input fields thinking maybe that would be the issue, but it still won't work.</p>
  
  <p>I then tried copy/pasting the following simple example into my application, and even that won't work at all:
  <a href="http://blog.angular-university.io/introduction-to-angular-2-forms-template-driven-vs-model-driven/" rel="nofollow noreferrer">http://blog.angular-university.io/introduction-to-angular-2-forms-template-driven-vs-model-driven/</a></p>
  
  <p>Any ideas as to what might prevent it from working correctly?</p>