bug#18335: 24.4.50; Typo: title of `enriched.txt' is `enriched.el'

[Drew Adams]

> > the title remains `enriched.el'.
> 
> It's describing the features of enriched.el.

Well of course it does that - anything that describes Enriched mode
does that.  But it certainly is not describing `enriched.el'. 
It tells you nothing about the code.

And Emacs does not introduce this file to its users as something
that describes `enriched.el'.  Not at all.  This is how Emacs
introduces the file to users - in (emacs) `Enriched Text':

  The file `enriched.txt' in Emacs's `data-directory' serves as an
  example of the features of Enriched mode.
  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

The file serves as our primary example, for ordinary users (not
necessarily Lispers), of Enriched mode.  It is end-user doc about
Enriched mode.  It is not an explanation or description of
`enriched.el'.