Sat Apr 30 23:18:35 EDT 2011

Lambda & app.

Q: shouldn't closures be bound in the environment?

Currently they are expected as a direct argument of app (in code) but
that can't work because closures can only be the result of a lambda
expression evaluation (make-closure).

So I have to fix that in the VM (trivial: add deref) and in the test

EDIT: fixed