title: Angular2 setTimeout returning ZoneTask rather than a "Number"
body: <p>Trying to use setTimeout in angular2 and I want to clear the timeout later.</p>
  
  <p>But Angular2 is returning a "ZoneTask" rather than a number</p>
  
  <pre><code>constructor() {
      this.name = 'Angular2'
      this.timeoutId = setTimeout(() =&gt; {  
        console.log('hello');
      }, 2000);
  
  
      console.log("timeout ID---", this.timeoutId); // Output - ZoneTask {_zone: Zone, runCount: 0, _zoneDelegates: Array[1], _state: "scheduled", type: "macroTask"…}_state: "notScheduled"_zone: Zone_zoneDelegates: nullcallback: function () {cancelFn: nulldata: Objectinvoke: function () {runCount: 0scheduleFn: function scheduleTask(task) {source: "setTimeout"state: (...)type: "macroTask"zone: (...)__proto__: ZoneTask app.ts:24
  
    }
  </code></pre>
  
  <p>How do I use the normal setTimeout or what is the preferred to use  setTimeout and then clearTimeout in Angular2?</p>
  
  <p><a href="https://plnkr.co/edit/DBMDpx62VrsClKdqPvmq?p=preview" rel="noreferrer">Plunkr here</a></p>