title: Dateformatter issue in swift
body: <p>My API sending me date string in UTC like 2/20/2016 11:45 AM.
  For displaying date in my timezone, I am converting date from UTC to Local time zone like below code </p>
  
  <pre><code>    let sourceDateString = "12/20/2016 11:45 AM"
      let formatter = DateFormatter()
       formatter.dateFormat = "MM/dd/yyyy hh:mm a"
       formatter.timeZone = TimeZone(identifier: "UTC")
       let date = formatter.date(from: sourceDateString)
  
       print(date)
  
       formatter.timeZone = NSTimeZone.local
       formatter.dateFormat = "MMM dd,yyyy hh:mm a"
  
       let strDate = formatter.string(from: date!)
       print(strDate)
  </code></pre>
  
  <p>Above code is working fine if my device time format is in 12 HR but if I am using 24 Hr date from my device then above code is not working. Event it's not able to convert UTC string to date.</p>
  
  <p>Please check above code in the device, it's working fine in simulator. </p>