bug#18086: 24.4.50; NEWS entry for `kill-region'

[Drew Adams <drew.adams@oracle.com>]

> From the beginning, and forever prior to Emacs 24.4, `kill-region' had
> this signature: (kill-region BEG END).  That includes Emacs 24.3.
> 
> Starting with Emacs 24.4, this is the signature:
> (kill-region BEG END &optional REGION)
> 
> 1. This change should be called out in NEWS.
> 
> 2. Instead, there is this entry in NEWS for Emacs 24.4, under
> "Incompatible Lisp changes in Emacs 24.4":
> 
> ** `kill-region' has lost its `yank-handler' optional argument.
> 
> This is incomprehensible.  It never had a `yank-handler' optional
> argument.

I was apparently wrong about that last statement (and so too about
the first statement, that in 24.3 the function accepted only two args).

[However, I do not really understand, and have no time to research
this now: in Emacs 24.3, emacs -Q, `C-h f kill-region' does NOT
show parameter YANK-HANDLER.  But in the 24.3 source file simple.el,
YANK-HANDLER is present.  Perhaps the simple.elc distributed by GNU
is older than the addition of YANK-HANDLER to simple.el?]

The NEWS entry should state not that the YANK-HANDLER parameter
was removed but that it was replaced by the REGION parameter etc.

And of course there SHOULD have been a NEWS entry for 24.3,
stating that parameter YANK-HANDLER was added.  If it is not too
late, that should be added now.  Without it, mention of YANK-HANDLER
in the 24.4 entry makes no sense.