Add Java and Python code for the following imgproc tutorials: Finding contours in your image, Convex Hull, Creating Bounding boxes and circles for contours, Creating Bounding rotated boxes and ellipses for contours, Image Moments, Point Polygon Test.

Add Java and Python code for the following features2d tutorials: Harris corner detector, Shi-Tomasi corner detector, Creating your own corner detector, Detecting corners location in subpixels, Feature Detection, Feature Description, Feature Matching with FLANN, Features2D + Homography to find a known object. Use Lowe's ratio test to filter the matches.

Add Java and Python code for the following imgproc tutorials: Affine Transformations, Histogram Equalization, Histogram Calculation, Histogram Comparison, Back Projection.

Add Java and Python code for the following imgproc tutorials: Canny, Remap, threshold and threshold inRange. Use HSV colorspace instead of RGB for inRange threshold tutorial.

* Custom deep learning layers support

* Stack custom deep learning layers

- CV_RGB() macro is moved into opencv2/imgproc.hpp from imgproc_c.h
- samples/cpp/filestorage_base64.cpp is dropped

also add comments explaining the change

- allow installing samples sources on all platforms
  even if BUILD_EXAMPLES is disabled,  fixed minor
  issues in sources installation process
- use 'example_<group>_<name>' scheme for target and binary file naming
- use single function for sample executable creation

- use per-module includes instead of "opencv.hpp"
- unused function warnings
- undefined macro warning

* Add a new interface for hough transform

* Fixed warning code

* Fix HoughLinesUsingSetOfPoints based on HoughLinesStandard

* Delete memset

* Rename HoughLinesUsingSetOfPoints and add common function

* Fix test error

* Change static function name

* Change using CV_Assert instead of if-block and add integer test case

* I solve the conflict and delete 'std :: tr1' and changed it to use 'tuple'

* I deleted std::tr1::get and changed int to use 'get'

* Fixed sample code

* revert test_main.cpp

* Delete sample code in comment and add snippets

* Change file name

* Delete static function

* Fixed build error

Found via `codespell -q 3 --skip="./3rdparty" -I ../opencv-whitelist.txt`

* Update samples

* Update calib3d.hpp

* Update calib3d.hpp

* Update calib3d.hpp

* Update calib3d.hpp