Test code for stack unwinding.
The explicit pointer stack now contains indirections to pointers on the stack.
The garbage collector builds with both LAR/semi-space representations.
Closing #endif comments.
Narrowed defunctionalization-specific flags (and fixed worng depth of apply() when formal scrutinees are enabled).
Correct handling of parentheses when printing function calls.
Bugfix: LARs are now pushed correctly to the explicit pointer stack for all kinds of functions.