title: Need to make two HTTP network requests simultaneously (with a completion handler once both finish)
body: <p>I have a situation where I need to make two HTTP GET requests and handle their results only after both are finished. I have a completion handler on each individual network request but it isn't helpful as I don't know when data from both requests are retrieved.</p>
  
  <p>I have limited experience with GCD but now that Swift 3 is out, I am trying to figure out how to run multiple tasks and have a single completion handler for them. My research has shown that GCD or NSOperationQueue may be the solution I'm looking for. Can anyone help suggest which tool fits the job and what the code might look like in Swift 3?</p>