title: Programmatically scroll a UIScrollView to the top of a child UIView (subview) in Swift
body: <p>I have a few screens worth of content within my UIScrollView which only scrolls vertically.</p>
  
  <p>I want to programmatically scroll to a view contained somewhere in it's hierarchy.</p>
  
  <p>The UIScrollView move so that the child view is at the top of the UIScrollView (either animated or not)</p>