* re-enabled NEON routines for arm64

http://www.libpng.org/pub/png/libpng.html

(2.4) Backports from master branch (#7854)

Enable SSE optimization

Pdb file support was changed in CMake 2.8.12, support was added in CMake 3.1.0 to work around the problems created by the change introduced in CMake 2.8.12.

- 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>

* cmake CMP0054 and CMP0045
* aarch64 build
* portable code options in PCH cmake
* some of gcc 4.9 warnings

(cherry picked from commit b75cbfde)

Conflicts:

	cmake/OpenCVModule.cmake

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

They're not listed in the documentation for the FindZLIB module,
so we shouldn't use them unless necessary.

for libpng added.