bug#23179: 25.0.92; Restore `M-,' to continue etags search

[Juri Linkov]

>> Another problem:
>>
>>    5. Files in the output of project-find-regexp are not sorted 
>> alphabetically,
>>       so currently the result is a mess in random order.
>
> Aren't they in the same order as find-grep outputs them? IOW, rgrep must
> have the same problem. I find it very minor, personally.
>
> We can add sorting here, but that would more or less preclude asynchronous
> generation/rendering of output we'd want to implement someday.

I tried to run rgrep in `emacs -Q' and see that its output is unsorted
indeed.  I forgot that I customized the sorting of the output long ago:

(setq grep-find-template
"find <D> <X> -type f <F> -print0 | sort -z | xargs -0 -e grep <C> --color -inH 
-e <R>")
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