title: How to join a collection of Promises asyncrounously in a Saga?
body: <p>Within a <code>redux</code> saga I am sending a half dozen fetch requests to different systems.  I want to wait until all those requests return, then do some final processing on the results.</p>
  
  <p>To this end I have an array of <code>promises</code>, representing each query.  I could call <code>Promise.all()</code> on the array, but this would cause the saga to hang, and thus all events to hang, until the promises return.</p>
  
  <p>I tried creating an <code>async promise</code> that called <code>promise.all</code>, then using the <code>redux-effects</code> Call on that promise, but this also hung.</p>
  
  <p>How can I keep the <code>async</code> nature of my saga while waiting for the promises to return?</p>