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/java/android_sdk/android_gradle_lib/AndroidManifest.xml

@@ -0,0 +1,4 @@
+<?xml version="1.0" encoding="utf-8"?>
+<manifest xmlns:android="http://schemas.android.com/apk/res/android"
+      package="org.opencv" >
+</manifest>

3rdparty/opencv-4.5.4/modules/java/android_sdk/android_gradle_lib/build.gradle

@@ -0,0 +1,58 @@
+apply plugin: 'com.android.library'
+@KOTLIN_PLUGIN_DECLARATION@
+
+def openCVersionName = "@OPENCV_VERSION@"
+def openCVersionCode = ((@OPENCV_VERSION_MAJOR@ * 100 + @OPENCV_VERSION_MINOR@) * 100 + @OPENCV_VERSION_PATCH@) * 10 + 0
+
+android {
+    compileSdkVersion @ANDROID_COMPILE_SDK_VERSION@
+
+    defaultConfig {
+        minSdkVersion @ANDROID_MIN_SDK_VERSION@
+        targetSdkVersion @ANDROID_TARGET_SDK_VERSION@
+
+        versionCode openCVersionCode
+        versionName openCVersionName
+
+        externalNativeBuild {
+            cmake {
+                arguments "-DANDROID_STL=@ANDROID_STL@"
+                targets "opencv_jni_shared"
+            }
+        }
+    }
+
+    buildTypes {
+        debug {
+            packagingOptions {
+                doNotStrip '**/*.so'  // controlled by OpenCV CMake scripts
+            }
+        }
+        release {
+            packagingOptions {
+                doNotStrip '**/*.so'  // controlled by OpenCV CMake scripts
+            }
+            minifyEnabled false
+            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.txt'
+        }
+    }
+
+    sourceSets {
+        main {
+            jniLibs.srcDirs = ['../../jni']
+            java.srcDirs = ['src']  // TODO Use original files instead of copied into build directory
+            aidl.srcDirs = ['src']
+            res.srcDirs = ['@OpenCV_SOURCE_DIR@/modules/java/android_sdk/android_gradle_lib/res']
+            manifest.srcFile 'AndroidManifest.xml'
+        }
+    }
+
+    externalNativeBuild {
+        cmake {
+            path (project.projectDir.toString() + '/libcxx_helper/CMakeLists.txt')
+        }
+    }
+}
+
+dependencies {
+}

3rdparty/opencv-4.5.4/modules/java/android_sdk/android_gradle_lib/res/values/attrs.xml

@@ -0,0 +1,11 @@
+<?xml version="1.0" encoding="utf-8"?>
+<resources>
+    <declare-styleable name = "CameraBridgeViewBase" >
+       <attr name="show_fps" format="boolean"/>
+       <attr name="camera_id" format="integer" >
+          <enum name="any" value="-1" />
+          <enum name="back" value="99" />
+          <enum name="front" value="98" />
+       </attr>
+    </declare-styleable>
+</resources>