Adding cl for when we need to compile defun* macro

I had trouble using the library due to not have the cl library loaded.  I believe its only needed for compiling that defun* macro following this Emacs Wiki entry:

http://www.emacswiki.org/emacs/CommonLispForEmacs

I added the this line to load it for compiling only:

    (eval-when-compile (require 'cl))