refactored gpu perf tests and fixed sanity tests
fixed gpu bitwise operations with scalars
fixed warp tests
fixed ffmpeg destination folder for NMake generator
fixed OpenCVConfig for cross-compilation:

* added CUDA to EXTRA libs if OpenCV uses it
* added -rpath-link option for linker if OpenCV was built as SHARED libs
Merge pull request #557 from jet47:gpu-sanity
Merge pull request #573 from jet47:config-cross-compilation
Merge pull request #578 from jet47:nmake-ffmpeg-copy