jextract example for Mac OS Frameworks

[guw]

Thanks for providing the samples. I am looking to extract source code for working with CoreFoundation/CoreFoundation.h and Security/Security.h. I think it's a matter of getting the include paths correct but I am not sure. They seem to be distributed in /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX.sdk/System/Library/Frameworks/