temporary relegation of new func display-message-timeout

[Teika Kazura <teika lavabit com>]

Hi. New function 'display-message-with-timeout' is brought in for
1.6. It is a very good function, but I'm planning to downgrade it to a
function without doc, nor annoucement in news.texi. It's only for the
1.6 release, and the even better one will be in 1.7.

I don't like current display-message. The only way to delete the
window for user seems clicking on it. (I once was upset I couldn't
delete it. Esc nor Enter doesn't work.)  The appearance is a bit
shabby, and fonts, color, etc can't be changed. This situation can be
fixed.  Default timeout can be one of such options, so there's no need
of seperate function 'display-message-with-timeout'. One,
'display-message' which accepts timeout too suffices.

There're similar devices. Namely, the prompt, and the window for
cycling which shows the cycled window name & icon. I think default
fonts, color can be common for all of display-message, prompt, etc.
(It may be better if user can choose different properties for each of
them.)

But the whole rewritement requires a lot. First, we have to design the
goal. Recoding follows. I don't want to do them all for 1.6. Better
design wins. This is why I don't like to have
display-message-without-time, a halfway achivement, open to public in
1.6.

It is used in two places, so what I'll do is to put "Don't use
this. display-message will have timeout option in 1.7".

If you have any idea, please let us know it. Regards,
Teika (Teika kazura)