title: Get UIImage only with Kingfisher library
body: <p>I need to get a UIImage only instead of loading a normal UIImageView with <a href="https://github.com/onevcat/Kingfisher" rel="noreferrer">Kingfisher library</a> </p>
  
  <p>To realize it I implemented a workaround with UIImageView:</p>
  
  <pre><code>let imageView = UIImageView()
  
  imageView.kf_setImageWithURL(NSURL(string: cpa.imageName)!, placeholderImage: nil,
          optionsInfo: [.Transition(ImageTransition.Fade(1))],
          progressBlock: { receivedSize, totalSize in
              print("\(receivedSize)/\(totalSize)")
          },
          completionHandler: { image, error, cacheType, imageURL in
              anView!.image = image //anView IS NOT an UIImageView
              anView!.frame.size = CGSize(width: 15.0, height: 15.0)
              print("Finished")
      })
  </code></pre>
  
  <p>This code works perfectly, but I would like to do it in a cleaner way.
  Is there a method in this library to get an UIImage only? Async and cached</p>