Add on-device text recognition (iOS)

LocalTextRecognition.swift

lazy var textDetector: VisionTextDetector = Vision.vision().textDetector()

func runTextRecognition(with image: UIImage) {
    let visionImage = VisionImage(image: image)
    
    textDetector.detect(in: visionImage) { (features, error) in
        if let error = error {
            print("Received error: \(error)")
        }

        self.processResult(from: features, error: error)
    }
}