bug#51733: 27.1; Detect impossible email addresses better

[Eli Zaretskii]

> Date: Mon, 17 Jan 2022 12:18:44 +0200
> From: Eli Zaretskii <eliz@gnu.org>
> Cc: 51733@debbugs.gnu.org, jidanni@jidanni.org
> 
> It is confusing to have 2 separate properties of a character that are subtly 
> incompatible, and for such obscure properties at that.  It will be source of 
> many problems.  So I think we should avoid that if it's feasible.  Can we 
> plrase discuss any real problems that would be xaused by using the existing 
> char-table?

I've now wrote a Lisp program to produce script property according to
Unicode vs what we have in char-script-table, so it's possible to see
all the differences.