Reworked build scripts for Android Java API, tests and examples

samples/android/tutorial-3-native/CMakeLists.txt

@@ -0,0 +1,6 @@
+set(sample example-tutorial-3-native)
+
+add_android_project(${sample} "${CMAKE_CURRENT_SOURCE_DIR}" SDK_TARGET 11 ${ANDROID_SDK_TARGET} NATIVE_DEPS opencv_features2d)
+if(TARGET ${sample})
+  add_dependencies(opencv_android_examples ${sample})
+endif()

samples/android/tutorial-3-native/default.properties

@@ -1,2 +0,0 @@
-# Project target.
-target=android-8

samples/android/tutorial-3-native/project.properties

@@ -1,2 +0,0 @@
-# Project target.
-target=android-11