func scaledToFillSize(size: CGSize, scale: CGFloat = 0) -> UIImage {
        let fitScale: CGFloat = max(size.width / self.size.width, size.height / self.size.height)
        let width: CGFloat = self.size.width * fitScale
        let height: CGFloat = self.size.height * fitScale
        let imageRect: CGRect = CGRectMake((size.width - width) / 2.0, (size.height - height) / 2.0, width, height)

        UIGraphicsBeginImageContextWithOptions(size, false, scale)
        self.drawInRect(imageRect)
        let newImage: UIImage = UIGraphicsGetImageFromCurrentImageContext()!
        UIGraphicsEndImageContext()

        return newImage
    }