bug#12443: 24.2.50; Default values in the minibuffer prompt (fix inconsisntecy)

[Drew Adams]

> > I see no reason for this inconsistency,
> 
> Agreed.  The officially sanctioned behavior is to use "(default ...)".

> > neither I see the need for the "default " part.
> 
> That would make the job of minibuffer-electric-default-mode harder
> (more false positives).

No offense to Miles or anyone else, but that mode is just a workaround for the
bother introduced by Emacs adding `(default ...)' here and there (but not yet
everywhere).  Just get rid of the cause, instead of sticking a band-aid on the
wound.

> > So, hereby I propose to fix this, i.e., to omit the "default " in
> > those commands where this is currently shown.
> 
> I find the "(default ...)" text to use up too much space for 
> my own taste, so I use the patch below to rewrite it on-the-fly
> to "[...]".

Just get rid of "(default ...)" altogether.  A user can use `M-n' to see the
default value, and `M-n RET' instead of `RET' to choose it.  No big deal, and a
lot less noise.

---

Or do as I do in Icicles: give users the choice, across all minibuffer prompts.
They have an option, with these possible values:

nil               - Do not insert default value
                    or add it to prompt.
t                 - Add default value to prompt
                    (except for `read-file-name' and
                    `read-from-minibuffer').
                    Do not insert it.
`insert-start'    - Insert default value
                    and leave cursor at start.
`insert-end'      - Insert default value
                    and leave cursor at end.
`preselect-start' - Insert and preselect default value;
                    leave cursor at beginning.
`preselect-end'   - Insert and preselect default value;
                    leave cursor at end.

The default value of the option is `t' (mainly to be closer to what people are
used to in vanilla Emacs).  But what I am suggesting for Emacs is the `nil'
behavior as default: do nothing with the default value.  (Personally, I use
`insert-end'.)