bug#1411: errors message upon exit disappear along with emacs

[jidanni]

I noticed when exiting emacs there was some error message in the
minibuffer, but it disappeared along with emacs before I could read it.

Let's see, I can sort of reproduce it here,
(and(message "Wait, Holmes!")(save-buffers-kill-emacs))
but that's only a guess.

You might say that every message should have a pause 1 second function
after it.

Anyways, not every message expects that it will have
save-buffers-kill-emacs right after it.

Well, maybe just the save-buffers-kill-emacs command should have a
pause 1 second command before it.

Or it should check the messages buffer at its start and finish, and if any
thing unexpected accumulates spew them onto stderr and exit, or
better: pause with "there were these messages, still exit? (y or n).

Or maybe emacs just shouldn't erase the screen... Hmmm, but in X
windows we want to close the window though. Stderr errors would end up
unnoticed in .xsession-errors probably...