calib3d: add stereoCalibrateExtended (#10667)

* cvCalibrateCamera2Internal: simplify per view error computation

* calib3d: add stereoCalibrateExtended

- allow CALIB_USE_EXTRINSIC_GUESS
- returns per view errors

* calib3d: add stereoCalibrateExtended test

* Newton's method can be more efficient

when we get the result of function distortPoint with a point (0, 0) and then undistortPoint with  the result, we get the point not (0, 0). and then we discovered that the old method is not convergence sometimes. finally we have gotten the right values by Newton's method.

* modify by advice  Newton's method...#10574

* calib3d(fisheye): fix codestyle, update theta before exit EPS check

This reverts commit 5384a220.

Allow to use 3 points in SolvePnP if SOLVEPNP_ITERATIVE and useExtrinsicGuess==true. Add bibtex citations for P3P. Update SolvPnP tests.

If there are no OpenCL/UMat methods calls from application.

OpenCL subsystem is initialized:
- haveOpenCL() is called from application
- useOpenCL() is called from application
- access to OpenCL allocator: UMat is created (empty UMat is ignored) or UMat <-> Mat conversions are called

Don't call OpenCL functions if OPENCV_OPENCL_RUNTIME=disabled
(independent from OpenCL linkage type)

it will allow to build features2d even if flann module is not available

about the same speed, but significatly more readable

Use directly solvePnP when the number of input points is equal to the number of model points. Enable useExtrinsicGuess parameter. Return rvec and tvec estimated using all the inliers instead of the best rvec and tvec estimated during the Minimal Sample Sets step. Document the behavior of solvePnPRansac.

Remove unnecessary Non-ASCII characters from source code (#9075)

* Remove unnecessary Non-ASCII characters from source code

Remove unnecessary Non-ASCII characters and replace them with ASCII
characters

* Remove dashes in the @param statement

Remove dashes and place single space in the @param statement to keep
coding style

* misc: more fixes for non-ASCII symbols

* misc: fix non-ASCII symbol in CMake file

The old error message was not giving any hint which input array (image)
led to an ill conditioned matrix. This made it near impossible to
identify poor images in a larger set.

A better approach would be to implement a checker function which gives
each image a rating before the real calibration is performed. This could
also include some image properties like sharpness, etc.

Enable p3p and ap3p in solvePnPRansac (#8585)

* add paper info

* allow p3p and ap3p being RANSAC kernel

* keep previous code

* apply catrees comment

* fix getMat

* add comment

* add solvep3p test

* test return value

* fix warnings