[racket] interactive.rkt

I have revised my interactive hack -- it's now fully racketized, and
has more features than before:

  http://barzilay.org/misc/interactive.rkt

This is mostly useful for people who do a lot of developement on a
command-line racket.

-- 
          ((lambda (x) (x x)) (lambda (x) (x x)))          Eli Barzilay:
                    http://barzilay.org/                   Maze is Life!