bug#23649: 24.5; `customize-mode'

[Eli Zaretskii]

> From: Noam Postavsky <npostavs@users.sourceforge.net>
> Date: Fri, 24 Jun 2016 23:14:08 -0400
> 
> >   Example mode-string, corrected:
> >
> >    "Customize options related to a major or minor mode.
> > By default the current major mode is used.
> > With a prefix argument or if the current major mode has no known group,
> > you are prompted for the MODE to customize."
> > 3. The prompt is thus incorrect as well: the candidates are not
> >    necessarily major-mode names.  It should just say "Mode: ".
> 
> Looks good to me, so I propose to push the attached patch with this
> docstring (and removal of "Major" from the prompts) to emacs-25. Any
> objections?

No, please push to master.

Thanks.