Added two kernels to existing SVM framework
Histogram intersection kernel (accessible by using SVM::INTER in CV namespace as kernel_type)
Exponetial chi2 kernel (accessible by using SVM::CHI2 in CV namespace as kernel_type)

Formulars:
Exp-CHI2
k(x,y) = exp(-gamma * CHI2(x,y))
CHI2(x,y) = 1- 2* SUM_i[(xi-yi)²/(xi+yi)]

Intersec
k(x,y) = SUM_i[min(xi,yi)]
Changed line 1266 in svm.cpp to allow the new kernels to be used
updated OpenGL functionality:

* removed OpenGLFuncTab, now extensions are loaded internally
* added support of GlBuffer and GlTexture2D to InputArray/OutputArray
* added ELEMENT_ARRAY_BUFFER and PIXEL_PACK_BUFFER targets
* added copyFrom/copyTo method for GlBuffer and GlTexture2D
* removed GlFont
* removed pointCloudShow
* removed OpenGLCleanCallback
* added Access parameter to GlBuffer::mapHost
* added autoRelease parameter to all create methods
Tutorial for ARM Linux cross compilation added.
add openCLExecuteKernelInterop method
Switched to TEST_CYCLE_MULTIRUN for fast tests
Increased time limits
Added Thin Prism Distortion Model

Only the code.
Thin prism distortion model added doc

Thin prism distortion model added to the
camera_calibration_and_3d_reconstruction.rst
optimized DeviceInfo class and ensureSizeIsEnough
Merge pull request #508 from bitwangyaoyao:2.4_interpKernel
Test system refactoring

cmpEps replaced on cmpEps2 to reduce code dublication;
Constants for cmpEps return values added.
Add auto detection to Intel OCL
cv::Ptr description extended.
restored binary compatibility
Merge pull request #512 from jet47:core-gpu-updates
Merge pull request #440 from AnnaKogan8:fixed-perfomance-tests
restored source compatibility
Fixed undistort.cpp
distCoeffs0 cols to 12