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

* Added accumulator value to the output of HoughLines and HoughCircles

* imgproc: refactor Hough patch

- eliminate code duplication
- fix type handling, fix OpenCL code
- fix test data generation
- re-generated test data in debug mode via plain CPU code path

* Add arguments to dftFilter2D

* test: add expected test values

- leads to errors due 'const' modifier of getMat() method
- may be non-optimal with non-CPU data storage

* imgcodecs cmake: the option to customize supported formats list (WITH_IMGCODEC_HDR, WITH_IMGCODEC_SUNRASTER, WITH_IMGCODEC_PXM)

* imgcodecs: fixes

- fixed CMake scripts (=OFF doesn't really work)
- restore dropped GDCM block
- added _IMGCODEC_ prefix
- fixed tests
- include PAM format under WITH_IMGCODEC_PXM option

- eliminate rand() calls
- non initialized members/ variables
- unused return values
- missing/useless NULL checks