adding Haar & LBP cascades perf test using UMat, removing old incomplete test
'master'-like Haar perf test
refactoring the test as it should be in 2.4
added perf tests for T-API warp operations
Added throwing exception when saving untrained SVM model
added perf tests for cv::blendLinear
added perf test for cv::cvtColor, pyr operations
added perf tests to some imgproc functions
added perf tests for filters
added perf tests for cv::dilate
added perf tests for cv::morphologyEx
added perf tests for cv::medianBlur
switching to `CL_PERF_TEST_P`, adding `safeFinish()` to flush CL queue
added perf test for cv::Moments
adding `finish()` to flush CL queue, renaming the test to match 'master' branch
fixed cv::integral perf test
added perf test for cv::sqrBoxFilter
Fix the following error for ocl::getOpenCLPlatforms() on Ubuntu 12.04 with gcc 4.8
OpenCV Error: Unknown error code -6 (OpenCL function is not available: [clGetPlatformIDs]) in opencl_check_fn, file /home/ahb/software/opencv/modules/ocl/src/cl_runtime/cl_runtime.cpp, line 83

The issue results from modules/ocl/src/cl_runtime/cl_runtime.cpp checking for
"linux" instead of "__linux__" (cp.  http://sourceforge.net/p/predef/wiki/OperatingSystems/)

Adjust all other occurrences of "defined(linux)" as well.
Merge pull request #2133 from apavlenko:2.4-perf_haar
deleted extra arg in case of power=0.5