docs: console.log() refer to util.format().

doc/api/stdio.markdown

@@ -9,30 +9,9 @@ Prints to stdout with newline. This function can take multiple arguments in a
 
     console.log('count: %d', count);
 
-The first argument is a string that contains zero or more *placeholders*.
-Each placeholder is replaced with the converted value from its corresponding
-argument. Supported placeholders are:
-
-* `%s` - String.
-* `%d` - Number (both integer and float).
-* `%j` - JSON.
-
-If the placeholder does not have a corresponding argument, `undefined` is used.
-
-    console.log('%s:%s', 'foo'); // 'foo:undefined'
-
-If there are more arguments than placeholders, the extra arguments are
-converted to strings with `util.inspect()` and these strings are concatenated,
-delimited by a space.
-
-    console.log('%s:%s', 'foo', 'bar', 'baz'); // 'foo:bar baz'
-
-If the first argument is not a format string then `console.log()` prints
-a string that is the concatenation of all its arguments separated by spaces.
-Each argument is converted to a string with `util.inspect()`.
-
-    console.log(1, 2, 3); // '1 2 3'
-
+If formating elements are not found in the first string then `util.inspect`
+is used on each argument.
+See [util.format()](util.html#util.format) for more infomation.
 
 ### console.info()