Rename #'-reader to function-reader.
Add a reader macro ^ for a shorthand of lambda.

^(coerce _ 'list)   <=> (lambda (x) (coerce x 'list))
^(* (sin (1+ _)) _) <=> (lambda (x y) (* (sin (1+ x)) y))
^(apply #'list _ (length _) _..)
  <=> (lambda (x y &rest z) (apply #'list x (length y) z))
Fix cl21.lazy. The behavior of cl21:append has changed.