* Add debug build option to MacOs and iOS build scripts

* osx: allow selection of MACOSX_DEPLOYMENT_TARGET

* Add --debug_info flag to iOS and macOS builds for building with debug info

Add ability to build iOS and macOS frameworks with nonfree modules (#13424)

* Allow building ios framework with nonfree

* Allow building osx framework with nonfree

Without it set, the build will choose the current OS version as the deployment target. 10.9 is the earliest usable, since that is when OS X introduced libc++.

This version uses CMake to generate Info.plist, which should be more
reliable than the old approach.

another fix to make OpenCV more friendly for iOS developers. We now use libc++ instead of libstdc++ and clang instead of gcc to build opencv2.framework.

for supporting with iOS 6 devices

always remove libopencv_world.a before building framework to always include the up-to-date code into the framework binary.

added script to build the universal opencv2.framework for iOS device and simulator. fixed opencv_world cmake script to create static libopencv_world.a for iOS. temporarily disable compressed file storages in the case of iOS (to avoid dependency of zlib)