Documentation/git-reset.txt: suggest git commit --amend in example.

In example 'Undo a commit and redo', refer to 'git commit --amend', as
this is the easier alternative.

Signed-off-by: Junio C Hamano <junkio@cox.net>

Documentation/git-reset.txt

@@ -67,6 +67,8 @@ message, or both.  Leaves working tree as it was before "reset".
 <3> "reset" copies the old head to .git/ORIG_HEAD; redo the
 commit by starting with its log message.  If you do not need to
 edit the message further, you can give -C option instead.
++
+See also the --amend option to gitlink:git-commit[1].
 
 Undo commits permanently::
 +