title: RxJS combineLatest on object of Observables?
body: <p>I've found myself with a mixed object of values and observables. Something like:</p>
  
  <pre><code>const mixedObject = {
    field1: "Hello",
    field2: Rx.Observable.of('World'),
    field3: Rx.Observable.interval(1000),
  };
  </code></pre>
  
  <p>What would be the best way of doing something like a <code>combineLatest</code> on this object to get a stream of plain objects. </p>
  
  <p>For example, I'd like to do something like:</p>
  
  <pre><code>Rx.Observable.combineLatest(mixedObject).subscribe(plainObject =&gt; {
    console.log(plainObject.field1, plainObject.field2, plainObject.field3);
    // Outputs: 
    // &gt; Hello World 0
    // &gt; Hello World 1
    // &gt; Hello World 2
  });
  </code></pre>