Create haarcascade_russian_plate_number.xml

Detector for russsian vehicle registration plate
Merge pull request #2747 from jet47:gpu-resize-stream-fix
Merge pull request #2749 from jet47:fix-bug-3678
exposed OpenCL-control functions to python
exposed TVL1 optical flow to python
Fixed build issues
Merge pull request #2743 from StevenPuttemans:bugfix_3549
Fix svm intro tutorial
Added condition to 1st test in cv::GaussianBlur

Consistent with the test made in cv::boxFilter, it adjusts the kernel size to the source size only if the border is not BORDER_CONSTANT and if BORDER_ISOLATED is set. Otherwise, the source has to be considered possibly in a larger image (i.e. the source being a ROI) in witch the kernel should apply.
use more accurate reshape
add additional tests for different input cases
IPP: fixed ipp_matchTemplate
optimized stitching warpers
Merge pull request #2756 from ElenaGvozdeva:ippi_matchTemplate
A more efficient workaround for erode
Optimized memory access by using stride pattern
T-API: optimized ocl_flip
fixed conditions
added performance test for cv::norm with NORM_RELATIVE
Merge pull request #2753 from shahurik:2.4