title: Form doesn't hide/show with *ngIf
body: <p>I simple want to toggle the visibility of a form with a button that changes the visibility variable:</p>
  
  <p>In the template:</p>
  
  <pre><code>&lt;button (click)="ChangeVariable()"&gt;I'm a button&lt;/button&gt;
  &lt;form *ngIf="variable"&gt;
   &lt;input type="text" [(ngModel)]="personName"/&gt;&lt;br&gt;
  &lt;/form&gt;
  </code></pre>
  
  <p>In the component:</p>
  
  <pre><code>variable : bool = false;
  ChangeVariable(){
   this.variable = !this.variable;
  }
  </code></pre>
  
  <p>The problem is that it shows the form, but later it doesn't hide it. Ever.</p>