This reverts commit 7349b8f5 (partially).

During the cluster-based detection of circle grids, the detected circle
pattern has to be mapped to 3D-points. When doing this the width (i.e.
more circles) and height (i.e. less circles) of the pattern need to
be identified in image coordinates.

Until now this was done by assuming that the shorter side in image
coordinates (length in pixels) corresponds to the height in 3D.
This assumption does not hold if we look at the pattern from
a perspective where the projection of the width is shorter
than the projection of the height. This in turn lead to misdetections in
although the circle pattern was clearly visible.

Instead count how many circles have been detected along two edges of the
projected quadrangle and use the one with more circles as width and the
one with less as height.

Fix distortion figure in calib3d. Positive radial distortion corresponds to pincushion distortion and negative to barrel distortion. Add another figure that illustrates the influence of k1 in the distortion effect.

Add a function that draws frame axes. Useful for debugging purpose and to check the correctness of the output of a pose estimation method.

* fix #12012

* Replace CV_StsBadFlag with Error::StsBadFlag

* trying to fix the custom AVX2 builder test failures (false alarms)

* fixed compile error with CPU_BASELINE=AVX2 on x86; raised tolerance thresholds in a couple of tests

* fixed compile error with CPU_BASELINE=AVX2 on x86; raised tolerance thresholds in a couple of tests

* fixed compile error with CPU_BASELINE=AVX2 on x86; raised tolerance thresholds in a couple of tests

* seemingly disabled false alarm warning in surf.cpp; increased tolerance thresholds in the tests for SolvePnP and in DNN/ENet

to allocate memory >2Gb

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

* Add Java overloads for each default argument

* Add "fisheye_" prefix for cv::fisheye:: functions and enums

* Add functionality to filter homography decompositions

* documentation + small refactor

* fix comparing int to size_t (compiler warning)

* fix whitespace issues

* clarification of function return values in documentation

* refactor of function parameters and change in loop nesting

* cleanup useless .h, fix size_t to int compare, small refactor

* fix documentation and whitespace

* change output from return value to outputarray parameter

* update function docs to reflect changes in parameters

* whitespace

* failing test

* fixed warnings related to extended initialisers and improper types

* initialize vectors from arrays

* initialize vectors from arrays part 2

* fix whitespace

* fix trailing whitespace

* Include <inttypes.h> in test_filter_homography_decomp.cpp, should fix 'uint8_t' : undeclared identifier error

* updated the test (made it shorter and providing better diagnostic) and significantly improved implementation (get rid of heavy repeated and/or unnecessary operations)

* fixed compile warning; removed trailing whitespace

* StereoBM: fixed SIMD processing for fixed-type output arrays

* changed norm type and threshold, added assertion

* fixed disp_shift

fixes handling of empty matrices in some functions (#11634)

* a part of PR #11416 by Yuki Takehara

* moved the empty mat check in Mat::copyTo()

* fixed some test failures