This commit introduces a POM.xml file to allow the build of OpenCV and Java bundles using Maven.

An additonal directory has been created  'platforms/maven' to contain the POM and scripts used during the build process. An additional Markdown file is included to give instructions on how to build with Maven.

The INSTALL_NAME_DIR property of a target specifies how a dynamic library should
be found on OS X.  If INSTALL_NAME_DIR is not specified the loader will search
relative to the standard search paths.  If specified it should either be
an absolute path or relative path prefixed with either @executable_path,
@load_path, or @rpath.  Specifying "lib" does not make sense here and
causes linking error as documented here:

http://answers.opencv.org/question/4134/cmake-install_name_tool-absolute-path-for-library-on-mac-osx/

and here

http://stackoverflow.com/questions/26978806/dyld-library-not-loaded-lib-libopencv-core-3-0-dylib-reason-image-not-found

This patch removes INSTALL_NAME_DIR everywhere it is set to "lib".
An alternate solution would be to set an absolute path like
"${CMAKE_INSTALL_PREFIX}/lib" or relative path like
"@executable_path/../lib".  However, if there is not specific need for
specifying a path, it is probably best left unset.

and fix the compilation for iOS in the same time

The Android NDK would be moving to Clang as its default compiler
in the future. This patch allows OpenCV to build with the default
c++_shared / c++_static

TEST=Builds OpenCV with -DANDROID_TOOLCHAIN_NAME=
aarch64-linux-android-clang3.6 -DANDROID_STL=c++_shared

Conflicts:
	modules/ts/misc/run.py

- IPP is disabled by default when compiler is mingw (couldn't make it
work)
- fixed some warnings
- fixed some `__GNUC__` version checks (for correctness and convenience)
- removed UTF-8 BOM from hough.cpp (fixes #5253)

Add Android HardFP support. Expose the "armeabi-v7a-hard with NEON"
ANDROID_ABI.

TEST= Add -DANDROID_NATIVE_API_LEVEL=21
-DANDROID_ABI="armeabi-v7a-hard with NEON"

to compile with hardfp. Checked the output of make verbose to
confirm -lm_hard is being linked. There are known test
failures but that can be fixed once this is in.

of WINRT samples

This removes requirement to add OPENCV_WINRT_INSTALL_DIR with backslash in the end

in case trailing slash is presented VS handles duplicated slashes w/o issues