bug#31094: Code for second solution

[Boruch Baum <boruch_baum@gmx.com>]

On 2018-04-08 16:06, Eli Zaretskii wrote:
> Why not do this the other way around: make apropos-value present a
> shorter list when invoked with some special value of the prefix
> argument?  Or even make this a new command?  That way, people's muscle
> memory doesn't need to change, which I think is a Good Thing, given
> that I think we never had any complaints about the current behavior.

If either or both proposed changes are adopted, there will be no need to
change muscle memory for those who want the behavior to remain the same.

The first code snippet already only changes behavior when the function
is called with either two or three universal prefix args.

The second snippet is controlled by a boolean defcustom variable,
defaulting to the current long print-out behavior.

-- 
hkp://keys.gnupg.net
CA45 09B5 5351 7C11 A9D1  7286 0036 9E45 1595 8BC0