title: NSString boundingRectWithSize:options:attributes:context: not usable in Swift?
body: <p>I get the error...</p>
  
  <p><code>Could not find an overload for 'init' that accepts the supplied arguments</code> </p>
  
  <p>...when I try to use...</p>
  
  <pre><code>extension UIFont {
    func sizeOfString (string: String, constrainedToWidth width: Double) -&gt; CGSize {
      NSString(string).boundingRectWithSize(CGSize(width, DBL_MAX),
                                            options: NSStringDrawingOptions.UsesLineFragmentOrigin,
                                            attributes: [NSFontAttributeName: self],
                                            context: nil).size
    }
  }
  </code></pre>
  
  <p>Does <code>NSString</code> not support this method anymore, or am I messing up on the syntax?</p>