bug#10868: 24.0.93; `comment-style' needs to be explained

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

 
> > Read the bug #3370 thread, if you want to understand the problem.
> 
> Unfortunately, I did. It is long-winded and goes nowhere.
> I encourage everyone else not to bother.

Is it really so hard to understand?

 "the doc string for `comment-style' (which is pretty much
  useless) refers to `comment-styles', which is not
  recognized (and therefore has no link)."

emacs -Q

C-h v comment-style

 Style to be used for `comment-region'.
 See `comment-styles' for a list of available styles.

C-h v comment-styles

Bzzzzt -not recognized - no such variable, no such "list of available styles"
... until you load newcomment.el.

There is a user option (`comment-style'), which you can customize.  But its doc
tells you nothing useful.  It just refers you to an internal variable
(`comment-styles'), which has no doc until you load its library.

The doc for `comment-styles' _is_ helpful ... once it becomes available.

Here is a case where we actually autoload a user option, `comment-style', so its
(useless) doc is available prior to loading the library.

But that doc string just refers you to a variable (constant, actually) whose doc
(the advertised "list of available styles") is not available until you load the
library.

Bravo.  Thanks for helping users out.

> > There is no _explanation_ of `comment-style'.
> 
> Right, well, good luck with your future bug reporting.

So constructive.