title: Set global TimeZone for DateFormatter
body: <p>I searched here in SO but can't find useful thread to accomplish what I want. I'm new with Swift so I don't know much of this. So the scenario is I want to set a specific timezone which can be change by user with the app's settings. What I want is when the user changed the said timezone it should reflect through out the app. Yes I can set the timezone in each "DateFormatter" but I don't want to write it every time I create a DateFormatter.</p>
  
  <p>Is there a way so when I create an instance of the DateFormatter the timezone is already set to the timezone the user selected? Is it possible to do this using an Extension of the DateFormatter?</p>