remove the C3 kernels in arithm, as the oclMat will never store 3 channels data
merge add and sub into one set of kernels
#2813 bugfix
Minor code cleanings in lkdemo.cpp
Fixed the shebang lines on the Python scripts.

Also, removed the one from modules/python/src2/cv.py and cleared its
executable bit, since it's not a script.
changed reinterpret_cast to static_cast

This issue seem to be lingering around for quite some time
https://github.com/Itseez/opencv/pull/639
http://code.opencv.org/issues/2819
remove the OpenCL Dir finding in CMake
Replace create with ensureSizeIsEnough thus buffer objects can be reused.
Optimize bfmatcher by passing macros.
Further optimize bfmatcher by passing macros.
Fix build error on linux.
Rename test case category and code clean up.
Capitalize macro namings.
fix the compile errors on Mac
Merge pull request #781 from bitwangyaoyao:2.4_fixerr
Merge pull request #806 from bitwangyaoyao:2.4_fix
Merge pull request #807 from pengx17:2.4_ocl_bfm_opt
Merge pull request #801 from kirill-kornyakov:lkdemo-fix
Merge pull request #804 from gpsinghsandhu:staticCast
Merge pull request #808 from bitwangyaoyao:2.4_mac