This version is a bit more useful, and we should be able to get rid of the
Stack class. Also, the Ruamoko parts of the autorelease system should be
almost ready now.
It's probably nowhere near right, but probably ok for now (I need to study
the GNUStep code). I'm unhappy with the menu code hook, but it will have
to do for now.
class with the same name. This will break things. To support it, there are
three new classes, one of which is incomplete (AutoreleasePool). It'll get
finished soonish, but the rest of the class lib will need some updating to
work.