feat: 切换后端至PaddleOCR-NCNN，切换工程为CMake

1.项目后端整体迁移至PaddleOCR-NCNN算法，已通过基本的兼容性测试
2.工程改为使用CMake组织，后续为了更好地兼容第三方库，不再提供QMake工程
3.重整权利声明文件，重整代码工程，确保最小化侵权风险

Log: 切换后端至PaddleOCR-NCNN，切换工程为CMake
Change-Id: I4d5d2c5d37505a4a24b389b1a4c5d12f17bfa38c

3rdparty/opencv-4.5.4/modules/imgcodecs/misc/objc/ios/Mat+Converters.mm

@@ -0,0 +1,44 @@
+//
+//  Mat+Converters.mm
+//
+//  Created by Giles Payne on 2020/03/03.
+//
+
+#import "Mat+Converters.h"
+#import <opencv2/imgcodecs/ios.h>
+
+@implementation Mat (Converters)
+
+-(CGImageRef)toCGImage {
+    return MatToCGImage(self.nativeRef);
+}
+
+-(instancetype)initWithCGImage:(CGImageRef)image {
+    return [self initWithCGImage:image alphaExist:NO];
+}
+
+-(instancetype)initWithCGImage:(CGImageRef)image alphaExist:(BOOL)alphaExist {
+    self = [self init];
+    if (self) {
+        CGImageToMat(image, self.nativeRef, (bool)alphaExist);
+    }
+    return self;
+}
+
+-(UIImage*)toUIImage {
+    return MatToUIImage(self.nativeRef);
+}
+
+-(instancetype)initWithUIImage:(UIImage*)image {
+    return [self initWithUIImage:image alphaExist:NO];
+}
+
+-(instancetype)initWithUIImage:(UIImage*)image alphaExist:(BOOL)alphaExist {
+    self = [self init];
+    if (self) {
+        UIImageToMat(image, self.nativeRef, (bool)alphaExist);
+    }
+    return self;
+}
+
+@end