Restore OpenCL branch for minmaxLoc on float data
CPU (non-OpenCL) CLAHE now supports CV_16UC1.
Remove mul24, for CV8UC3 3840x2160 it generates implementation specific result
Merge pull request #3073 from vbystricky:ocl_fixMinMaxLoc
Merge pull request #3033 from nathanjackson:clahe_datatypes