ObjFW  GUI framework - call for help!

There now is a first working state of the generator for CoreGTK ported to ObjFW that was renamed to ObjGTK over [here](https://codeberg.org/Letterus/objgtkgen).

The example app [is working](https://kirche.social/@letterus/107028320037357684). For everything else (memory management, ARC) there still is some work to do.

I first want to get MRC memory management right and then try to make the generator more general so that it may work on more of the GTK classes and libs. Especially I'd like to generate wrappers for libgranite and libhandy which are important for modern desktop and mobile app development. But same applies to more of the GTK/GLib/GNOME libs probably.