add info about isearch-query-replace* to the isearch-forward docstring

[Dan Nicolaescu]

It would be nice to have the new isearch-query-replace* bindings
documented in the docstring. 

May I check this in? 


Index: isearch.el
===================================================================
RCS file: /cvsroot/emacs/emacs/lisp/isearch.el,v
retrieving revision 1.255
diff -c -3 -p -c -r1.255 isearch.el
*** isearch.el  16 Feb 2005 09:41:02 -0000      1.255
--- isearch.el  18 Feb 2005 06:53:13 -0000
*************** Type \\[isearch-quote-char] to quote con
*** 537,542 ****
--- 537,547 ----
  \\[isearch-abort] when search is successful aborts and moves point
  to\
   starting point.

+ Type \\[isearch-query-replace] to start `query-replace' with string to\
+ replace from  last search string.
+ Type \\[isearch-query-replace-regexp] to start `query-replace-regexp'\
+ with string to replace from last search string..
+
  Type \\[isearch-toggle-case-fold] to toggle search case-sensitivity.
  Type \\[isearch-toggle-regexp] to toggle regular-expression mode.
  Type \\[isearch-edit-string] to edit the search string in the
  minibuffer.