Merge pull request #1 from Itseez/2.4

2.4
remove unused variable in loadFromXML()
remove unused variable in HOGDescriptor::groupRectangles()
remove unused variable in findCorners_caller()
remove unused variable in ocl_moments()
remove unused variable in OCL_PERF_TEST_P()
remove unused variable in TEST_P()
remove unused variables in CV_KDTreeTest_CPP::findNeighbors()
Merge pull request #2603 from maksqwe:unused_fix_2.4