[Android] Update ui module structure. (#706)

* Remove redundant code for segmentation.

* Classification Documentation and example improvement.

* Ocr Documentation and example improvement.

* 1.detection、face、seg module add "svPreview.enableCamera();".
2.java/android add fastdepolyUi module.

* examples/vision/ to add OCRv3.

* Modify UI directory name.

* Refresh examples\vision,change OCR README.md

* Update ui module

* Update ui module

Co-authored-by: DefTruth <31974251+DefTruth@users.noreply.github.com>

java/android/ui/proguard-rules.pro

@@ -0,0 +1,21 @@
+# Add project specific ProGuard rules here.
+# You can control the set of applied configuration files using the
+# proguardFiles setting in build.gradle.
+#
+# For more details, see
+#   http://developer.android.com/guide/developing/tools/proguard.html
+
+# If your project uses WebView with JS, uncomment the following
+# and specify the fully qualified class name to the JavaScript interface
+# class:
+#-keepclassmembers class fqcn.of.javascript.interface.for.webview {
+#   public *;
+#}
+
+# Uncomment this to preserve the line number information for
+# debugging stack traces.
+#-keepattributes SourceFile,LineNumberTable
+
+# If you keep the line number information, uncomment this to
+# hide the original source file name.
+#-renamesourcefileattribute SourceFile