title: Ionic Forms with ngModel
body: <p>I have a form I want to map to an model object. When I add <code>[[ngModel]]</code> to the <code>ion-input</code>, the page does not load (no errors). </p>
  
  <p><strong>html</strong></p>
  
  <p><code>&lt;ion-input type="text" [(ngModel)]="personModel.username" formControlName="username" id="username"&gt;&lt;/ion-input&gt;</code></p>
  
  <p><strong>ts</strong></p>
  
  <pre><code>private personModel: PersonModel = null;
  this.personModel = this.navParams.get('personModel');
  </code></pre>
  
  <p>Any ideas why the <code>[[ngModel]]</code> is not working?</p>
  
  <p>Thanks</p>