bug#37812: Update Emacs manual intro with more compelling features

[Eli Zaretskii]

> From: Nicholas Drozd <nicholasdrozd@gmail.com>
> Date: Fri, 18 Oct 2019 12:50:46 -0500
> 
> The introduction to the Emacs manual says, right near the beginning:
> "We call Emacs 'advanced' because it can do much more than simple
> insertion and deletion of text.  It can control subprocesses, indent
> programs automatically, show multiple files at once, and more."
> 
> This text has been around for a long time*. Maybe it's time for an
> update? Indenting programs automatically and showing multiple files at
> once aren't very compelling features these days. My go-to example of a
> remarkable Emacs-y feature is EWW, so maybe "browse the Web" could be
> added? Or something to do with Org mode? I don't know exactly, but
> listing "shows multiple files" as a feature is like describing someone
> as "punctual" in a reference letter -- it could signal that the person
> has no other important qualities.

EWW and Org are very high-level Lisp applications, they aren't
examples of basic features of Emacs as an editor.  So I'm not sure
they are appropriate in that introductory section.

Richard, do you have any proposals for how to modify this description?
We still want to say that Emacs is an advanced editor, I'm sure.

We could also leave that text as it is: the fact that there are other
advanced editors nowadays with similar features doesn't mean that
Emacs isn't advanced, and there are certainly simple editors in use
that don't have the features we list as "advanced".

Thanks.