bug#8531: 24.0.50; shell-quote-argument shouldn't escape special characters

[Eli Zaretskii]

> From: Glenn Morris <rgm@gnu.org>
> Cc: thierry.volpiatto@gmail.com,  8531@debbugs.gnu.org
> Date: Fri, 22 Apr 2011 03:10:39 -0400
> 
> Eli Zaretskii wrote:
> 
> > Doesn't Eshell support the standard shell feature whereby a
> > non-special character escaped by a backslash stands for itself?
> 
> From reading the comments in eshell-parse-backslash, no.

IMO, the reasons stated in those comments for not supporting escaped
non-special characters are bad a design decision.  Eshell should only
do that on Windows, and even then there should be a user option for
such behavior, the default being that the directory separator is a
forward slash.

IOW, Eshell should behave like a Posix shell, even on Windows.