I would like to convert string-equal and string-lessp to
(defun string-equal s1 s2 &optional ignore-case) and
(defun string-lessp s1 s2 &optional ignore-case), respectively.
The goals are 1) to provide more consistent interface similar
to compare-strings and 2) to avoid an endless and annoying Elisp
up/downcasing like:

(defun gnus-string< (s1 s2)
   "Return t if first arg string is less than second in lexicographic order.
Case is significant if and only if `case-fold-search' is nil.
Symbols are also allowed; their print names are used instead."
   (if case-fold-search
       (string-lessp (downcase (if (symbolp s1) (symbol-name s1) s1))
                     (downcase (if (symbolp s2) (symbol-name s2) s2)))
     (string-lessp s1 s2)))

Note that unlike previous compare-strings change, this shouldn't break
backward compatibility.

Objections?

Dmitry