Duck util-format.

doc/utils.md

@@ -125,20 +125,6 @@ Returns ```#t``` if both dictionaries contain the same keys and their
 values are equal according to the provided ```equality?``` predicate
 which defaults to ```equal?```.
 
-### Format
-
-    (import util-format)
-
-A simple module with less-common formatting functions.
-
-    (format-amount amt)
-
-* ```amt``` - a number
-
-Converts given number to a string with two-digit fractional
-part. Should the fractional part be 0, it is replaced with the string
-"--".
-
 ### Mail
 
     (import util-mail)