Names for control characters (Was: "(in 6429)" in allkeys.txt)

[Eli Zaretskii]

> Date: Wed, 12 Mar 2014 17:36:37 +0000
> From: Selvaraju Anbu Kaveeswarar <anbu at cyberservices.com>
> Cc: "Whistler, Ken" <ken.whistler at sap.com>, starback at stp.lingfil.uu.se, unicode at unicode.org
> 
> Unicode 1 names are deprecated and the new names are in their place.

Obviously, the new names are useless when they are null.  Emacs lets
users specify a character by its name, so it uses aliases for
characters whose Name property is a null string.