Suggest slight change in description of Slug

[Tim Bray <Tim.Bray@xxxxxxx>]

I think 9.7 is subtly wrong.  I discovered this when I was shaking  
down the Ape's interaction with Joe's apptest server.  I sent a slug  
along and it didn't show up in the Member URI, so I complained.  I  
talked to Joe and found that we agreed that the whole point of "slug"  
is to affect the URI the world sees, not the one your editor sees.   
So you'd want the URI that you find in the <link rel="alt"/> to have  
the slug in it.

So I would propose that 9.7 be re-written as follows:

=============================
Slug is a HTTP entity-header that when accompanying a POST to a  
Collection, constitutes a request by the client that its value be  
used as part of the URI normally used to retrieve the to-be-created  
Member Resource.

Servers MAY use the value of the Slug header when creating the URI  
normally used to retrieve the newly-created resource, for instance by  
using some or all of the words in the value for the last URI segment.  
Servers MAY also use the value when creating the atom:id or as the  
title of a Media Link Entry (see Section 9.6.).
==============================

Also then it would be nice if the example in 9.2.1 got a <link  
rel="alt" that used the slug.

 -Tim