Found via `codespell -i 3 -w --skip="./3rdparty" -I ../opencv-whitelist.txt`

To prevent this result:
    /usr/bin/ccache ccache <android-ndk-r16.1>/toolchains/arm-linux-androideabi-4.9/prebuilt/linux-x86_64/bin/arm-linux-androideabi-gcc ...
with:
    ccache: error: Recursive invocation (the name of the ccache binary must be "ccache")

- '-fvisibility' flag was updated
- PVAPI library detection was changed

This is VS2017 Preview. It makes sure the version is detected properly and the INSTALL target then correctly installs to x64/vc15 (the same as MSVC1910).

The latest version (5.1.1) of the gnu compiler returns just its major version ("5") when given the "-dumpversion" argument. Gnu compiler developers don't consider this to be an error. A workaround for this case has been made.

Without the fix, OpenCV will compile and silently copy the compiled libs/executables to a location not prefixed with arch/vc14, and OpenCV won't be picked up by find_package and OpenCVConfig.cmake.

MinGW-w64 always uses "w64" as vendor key which the previously
used check for "64" anywhere in the target triplet matched. This
would lead to MinGW-w64 setups always being treated as x64.

Turns out we do not even need this additional check since the
architecture has been correctly determined earlier in this file.
No need to do it again.

- 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>

The architecture has been correctly determined earlier in this
file. No need to do it again.

MinGW-w64 always uses "w64" as vendor key which the previously
used check for "64" anywhere in the target triplet matched. This
would lead to MinGW-w64 setups always being treated as x64.

Since we are actually interested in finding the "64" in the
triplet's operating system key, this fix makes sure to look for
"mingw64" and thus avoids the false match.

Fixes issue #3835. Credits to Lode Leroy for the original patch.

Allow to build samples via OpenCV binaries from distribution package
(find_package with OpenCV_DIR).