turn on testing support in root binary directory
rewrite add_test command for accuracy tests:

* use new syntax introduced in CMake 2.8.0
* set OPENCV_TEST_DATA_PATH enviroment property
disable CTest target for opencv_test_viz:

opencv_test_viz creates windows and waits until user close them,
it is not appropriate for automatic testing
add CTest targets for sanity tests
determine test category (Public vs Extra) based on module location
Fixed highgui drawing test

- changed image comparison technique
- removed old assert statements
Fixes for QNX 6.6 Neitrino support.
avoid pointer arithmetic on register memory in color conversion
increase epsilons for some tests, which functions use floating point arithm
minor fix for StereoCSBP data cost compute kernel and test
Merge pull request #3356 from jet47:ctest-support
Merge pull request #3366 from jet47:fix-gpu-cuda-7.0
Merge pull request #3363 from asmorkalov:qnx_support
Merge pull request #3362 from mshabunin:fix-drawing-24