RE: 900276502f..: Paul Eggert 2018-11-13 Act like POSIX sh if $HOME is relative

[Drew Adams]

> > Setting HOME="z:" says “Whichever is the current directory on drive Z
> 
> Emacs doesn't support drive-relative file names on Windows.  It never
> did.  It always interpreted "x:" as the root directory on drive x.

Whatever gets decided wrt this bug report, please ensure
that the Emacs docs make clear what the behavior is.

In particular, let's tell users that "Emacs doesn't
support drive-relative file names on Windows."  So,
e.g., it interprets "x:" as the root directory on
drive x.

(Perhaps the behavior is already documented, in which
case no change is needed - dunno.)