title: Time CountDown in angular 2
body: <p>I want to have a date countdown like this:</p>
  
  <p><a href="http://codepen.io/garethdweaver/pen/eNpWBb" rel="noreferrer">http://codepen.io/garethdweaver/pen/eNpWBb</a></p>
  
  <p>but in angular 2, I found this plunkr that adds 1 to a number each 500 miliseconds:</p>
  
  <p><a href="https://plnkr.co/edit/pVMEbbGSzMwSBS4XEXJI?p=preview" rel="noreferrer">https://plnkr.co/edit/pVMEbbGSzMwSBS4XEXJI?p=preview</a></p>
  
  <p>this is the code:</p>
  
  <pre><code>import {Component,Input} from 'angular2/core';
  import {Observable} from 'rxjs/Rx';
  
  @Component({
      selector: 'my-app',
      template: `
        &lt;div&gt;
          {{message}}
        &lt;/div&gt;
      `
  })
  export class AppComponent {   
  
    constructor() {
      Observable.interval(1000)
                .map((x) =&gt; x+1)
                .subscribe((x) =&gt; {
                  this.message = x;
                }):
    }
  }
  </code></pre>
  
  <p>But I want to have a date taking one second until reach 0.</p>