[GC] Printing and forwarding

1) Printing of dotted pairs is now correct.
2) Forwarding doesn't modify the from space.

It looks like shrinking an array doesn't work, but no big fat
clues yet.

The array type is basically a success except for that.
[STRINGLISP] The new environment is a success.

The array and builtin function types are almost perfect and clearly
the way to go. The array_set_size function seems to need a little work.