bug#1478: 23.0.60; doc string of custom-unlispify-*

[Drew Adams]

1. The doc string of `custom-unlispify-menu-entries' says only this:
 
 "Display menu entries as words instead of symbols if non-nil."
 
What menu entries? Which menu?
 
It took me a while, searching and experimenting, to find that this is
about the `Custom' menu's submenus. Please clarify what this is for in
the doc string.

2. The doc string of `custom-unlispify-tag-names' says only this:

 "Display tag names as words instead of symbols if non-nil."

What's a tag name? This won't make much sense to an Emacs user who isn't savvy
to Emacs Lisp, `defcustom' :type, and :tag. Please explain this
better. A simple illustrative example never hurts: show what happens if
it's nil vs if it's non-nil.

These doc strings are all the user has to go on, since these options are not
described in any manual.
 

In GNU Emacs 23.0.60.1 (i386-mingw-nt5.1.2600)
 of 2008-11-24 on LENNART-69DE564
Windowing system distributor `Microsoft Corp.', version 5.1.2600
configured using `configure --with-gcc (3.4) --no-opt --cflags -Ic:/g/include
-fno-crossjumping'