Re: doc elisp intro cross reference fixes

[Luc Teirlinck]

Per Abrahamsen wrote:

   These were all deliberate design choices.  Adding customize support to
   your Emacs Lisp code should be an easy and gradual process:

     <http://www.dina.dk/~abraham/custom/old-custom.html>

The material at that site seems to be old.  Customize has been an
important and well known part of Emacs for years now.  I believe that
to add customize support to one's Emacs Lisp code, one first should
read (elisp)Customization and then turn the appropriate defvar's into
defcustom's.  I do not see why that should be difficult or be done
"gradually".  Actually, defcustom's _can_ get tricky, but only if the
author wants to really optimize stuff.  The latter can often be very
useful, but would never seem to be absolutely necessary.

Sincerely,

Luc.