fixed many bugs related to Mat::getUMat(), asynchronous kernel execution etc. Also, played a bit with ocl::cvtColor vs cv::cvtColor performance

Conflicts:
	modules/ocl/src/arithm.cpp

Conflicts:
	.gitignore
	CMakeLists.txt
	doc/CMakeLists.txt
	modules/calib3d/src/stereosgbm.cpp
	modules/core/include/opencv2/core/mat.hpp
	modules/highgui/src/cap_openni.cpp
	modules/ml/include/opencv2/ml/ml.hpp
	modules/objdetect/src/hog.cpp
	modules/ocl/perf/perf_color.cpp
	modules/ocl/src/arithm.cpp
	modules/ocl/src/filtering.cpp
	modules/ocl/src/imgproc.cpp
	modules/ocl/src/optical_flow_farneback.cpp
	platforms/scripts/camera_build.conf
	platforms/scripts/cmake_android_all_cameras.py
	samples/cpp/Qt_sample/main.cpp
	samples/cpp/tutorial_code/introduction/windows_visual_studio_Opencv/Test.cpp

Fixed to use native C++ instead of C++/CX although it does require significantly more code, it goes along with the spirit of keeping the project in native C++

Update system.cpp

Cleaned up whitespace, removed redundant code and added edge cases for string cleanup

Update system.cpp

Fixed compiler warning over comma operator clause

Update system.cpp

NULL initialization

Update system.cpp

Fixed use of WindowsGetStringRawBuffer which returns internal pointer to buffer

Update system.cpp

Support C++/CX and native C++ through conditional compilation.  Fixed style - long lines, comma operators, long conditional.  Optimized string usage to use reference.

Update system.cpp

Fixed conditional compilation around include and library

Update system.cpp

Fixed trailing space

Update system.cpp

Cleaned up whitespace, removed redundant code and added edge cases for string cleanup

Update system.cpp

Fixed compiler warning over comma operator clause

Update system.cpp

NULL initialization

Update system.cpp

Fixed use of WindowsGetStringRawBuffer which returns internal pointer to buffer

Update system.cpp

Support C++/CX and native C++ through conditional compilation.  Fixed style - long lines, comma operators, long conditional.  Optimized string usage to use reference.

Update system.cpp

Fixed conditional compilation around include and library

Update system.cpp

Fixed trailing space