[racket] Package conflict while attempting to install Whalesong

Hi Jens and Jay,

My apologies!  I have not been following with recent Racket
development at all.  I don't know what the current state of the Racket
packaging system is.  I don't know what I should be doing to fix this,
and I don't have time unfortunately to really start learning the new
packaging system right now.

If the fix is quick and easy to apply, I'll be happy to do it.