bug#20992: 25.0.50; `virtual-dired': (1) doc typo, (2) unclear

[Drew Adams <drew.adams@oracle.com>]

1. Doc string:

"...If you have save..." should be "...If you have saved..."

2. It is not very clear just what "Virtual Dired mode" is.  Apparently
it is a minor mode.  But there is no minor-mode variable.  And the mode
command does not have `-mode' in the name, and it is not defined using
`define-minor-mode' (why)?  The major mode seems to be `dired-mode' (at
least for a virtual-dired buffer created from a Dired buffer).  But
there is no access to the major-mode lighter and its menu in the mode
line.  And the doc could be clearer wrt just what parts (e.g. commands)
of Dired mode are available and what parts are not. Also, the doc says
that the format is that of `ls -lR', but that suggests that the listing
is recursive, with subdirs inserted, which is not necessarily the case.
And it seems that the listing switches are taken from the Dired buffer
from which the virtual mode is derived.


In GNU Emacs 25.0.50.1 (i686-pc-mingw32)
 of 2014-10-20 on LEG570
Bzr revision: 118168 rgm@gnu.org-20141020195941-icp42t8ttcnud09g
Windowing system distributor `Microsoft Corp.', version 6.1.7601
Configured using:
 `configure --enable-checking=yes,glyphs CPPFLAGS=-DGLYPH_DEBUG=1'