Multi-tty NEWS info.

[Richard Stallman]

This item in NEWS is rather sketchy, and not entirely accurate.

    +*** New functions: frame-tty-name, frame-tty-type, delete-tty,
    +suspend-tty, resume-tty, terminal-id, terminal-parameters,
    +terminal-parameter, set-terminal-parameter,
    +modify-terminal-parameters, environment, let-environment

Could someone please add more information about these new functions?

The functions `frame-tty-name' and `frame-tty-type' do not in fact
exist.  (That is probably a good thing -- I wondered why you would
want to get that info out of a frame rather than a terminal.)
I deleted them from the list, and split it into groups that make
sense to document together.

Can someone please look thru the diffs and reliably find all the newly
added functions and variables, to make sure this list is complete?
(There may be some functions and variables that users shouldn't use.
It is right to omit them from NEWS.  But I want to be sure we
are not missing any that should be listed.)


Meanwhile, how do you find a frame's terminal?  I'd expect there is
a way to do that, but I can't see anything here that relates to it.