Remove vestigial char.* builtins

c/string.c

@@ -501,10 +501,6 @@ static struct builtinspec stringfunc_info[] = {
     { "char-downcase", builtin_char_downcase },
     { "char-alphabetic?", builtin_char_alphabetic },
 
-    { "char.upcase", builtin_char_upcase },
-    { "char.downcase", builtin_char_downcase },
-    { "char.alphabetic?", builtin_char_alphabetic },
-
     { "number->string", fl_numbertostring },
     { "string->number", fl_stringtonumber },
 

scheme-core/aliases.scm

@@ -66,8 +66,6 @@
 
 (define (char->integer c) (fixnum c))
 (define (integer->char i) (wchar i))
-;(define char-upcase #f)
-;(define char-downcase #f)
 (define char=? eqv?)
 (define char<? <)
 (define char>? >)