Objective-C FFI with starting wrapper for the Cocoa, AppKit and Foundation kits/frameworks

Notes:
* Tweaks to `tests.sh` enables testing some programs on OS X only.
* This is the foundation for more PRs.
* Most cocoa tests are UNDEFINED because they use log. I'll add more tests with simple strings in the future.
* More tests for the FFI are needed.

Je dois comprendre qu'Objective-C tente de faire de la concurrence à Lisp en remplaçant les parenthèses par des brackets ?