Modified sparse pyrlk optical flow to allow input of an image pyramid which thus allows caching of image pyramids on successive calls.
Added unsigned char support for 1, 3, 4 channel images.

- Substituted HAVE_WINRT with WINRT
- Fixed compilation issues in ocl.cpp and parallel.cpp
- Fixed compiler issue for WP8: "C2678: binary '+' : no operator found which takes a left-hand - Fixed gitignore
- Added #ifdef HAVE_OPENCL to remove compiler warnings in ocl.cpp
- Used NO_GETENV similar to '3rdparty\libjpeg\jmemmgr.c;
- Added ole32.lib for core module (for WindowsStore 8.0 builds)
- Made OpenCV_ARCH aware of ARM
Signed-off-by: Maxim Kostin <v-maxkos@microsoft.com>

* use opaque algorithm interfaces
* add stream support

it caused runtime failures

* it is the only place, where it is used
* no need to make this function public

it is generated by CUDA headers and we can't fix it

changed tests for tvl1 optflow
correction of a bug preventing compilation with cuda (fmin changed to fminf)

replaces tabs with spaces

removed legacy tests in cudaoptflow