title: Swift - Sorting By Date Issue
body: <p>I'm using <code>NSSortDescriptor</code>s to sort an <code>Array</code> by the date element. The date is set as <code>String</code> using a formatter which formats in the style : "dd/MM/yy HH:mm". This date element is stored inside dictionaries which are all stored in the array. Parts of my code for this are below:</p>
  
  <pre><code>// Date Formatting
  let currentTime = Date()
  let timeFormatter = DateFormatter()
  timeFormatter.locale = Locale.current
  timeFormatter.dateFormat = "HH:mm dd/MM/yy"
  let convertedTime:String! = timeFormatter.string(from: currentTime)
  
  // Descriptor
  let descriptorD: NSSortDescriptor = NSSortDescriptor(key: "Date", ascending: false)
  
  // Dictionary
  let newUserRecord = [
      "Name"  : enteredName!,
      "Score" : self.gameScore,
      "Date"   : convertedTime
  ] as [String : Any]
  
  // Sorting 
  newUserArray.sort(using: [descriptorD])
  </code></pre>
  
  <p>However my problem is the date is only being sorted by the time (HH:mm) and not taking in account the (dd/MM/yy) part. For example if I sort by the date and have a date of 13:12 19/11/16 and a date of 09:12 18/11/16 the 09:12 date will appear first even though it should be the 13:12 as it is a day later. How do I fix this?</p>