Most importantly, added support for multiple include directores,
but also did some general cleanup.

In these cases, just using print() is enough to ensure py2/3
compatibility.

e.g. <opencv2/core/core.hpp> become <opencv2/core.hpp>

Also renamed <opencv2/core/opengl_interop.hpp> to <opencv2/core/opengl.hpp>

Suppressed hundreds of useless MSVC warnings (can be reenabled setting cmake variable ENABLE_NOISY_WARNINGS to ON). Fixed some of remaining warnings.

lot's of changes; nonfree & photo modules added; SIFT & SURF -> nonfree module; Inpainting -> photo; refactored features2d (ORB is still failing tests), optimized brute-force matcher and made it non-template.

Better variant of OpenCVConfig.cmake generation; several smaller changes in the options section and Android build scripts

 [~] Automatically tracked dependencies between modules
 [+] Support for optional module dependencies
 [+] Options to choose modules to build
 [~] Removed hardcoded modules lists from OpenCVConfig.cmake, opencv.pc and OpenCV.mk
 [+] Added COMPONENTS support for FIND_PACKAGE(OpenCV)
 [~] haartraining and traincascade are moved outside of modules folder since they aren't the modules

Started top-level CMakeLists.txt file reorganization: cmake scripts are moved to separate folder; refactored BUILD_*, INSTALL_*, ENABLE_*, USE_*, WITH_* options.

added cv.py micro-module for backward compatibility with existing Python scripts using prev-gen Python API.

upgraded to FLANN 1.6. Added miniflann interface, which is now used in the rest of OpenCV. Added Python bindings for FLANN.