bug#19461: 25.0.50; doc of `display-buffer-*' functions that take ALIST arg

[Drew Adams]

> Saying what it is is non-trivial, see section 28.13.3 of the Elisp
> manual.  So I have no good idea how to do what you propose.

If saying what it is is non-trivial for the
maintainers, and I'm sure you're right about
that, then imagine the difficulty of a user to
understand what it is, especially if we do not
say what it is.

If it can be said only in the manual, then the
doc string can, I guess, just punt with a link
to the appropriate section of the manual.