bug#13649: boobytrapped dired-do-async-shell-command question

[Juri Linkov]

>> > A command is running in the default buffer.  Use a new buffer? (yes or no)
>> >
>> > Which is a boobytrapped question, as picking "no" will always end up in 
>> > failure...
>>
>> Ah, to you "no" means "don't use a new buffer"?  Yes, this is too ambiguous.
>> A better question would be:
>>
>>   A command is running in the default buffer.  Run in a new buffer? (yes or 
>> no)
>
> Still not clear, IMO (what "default buffer"? run what?).  How about
>
>   Shell output buffer is used by another command; run this command in a new 
> buffer (yes or no)?

I'd rather make the prompt short and add a "help" option
(e.g. "yes/no/help" or "y/n/h") that will display the full
explanation of all options with a link to their customization.