[XSCH] towards next draft

Hi Jeff

I've gone through the editors draft

http://www.w3.org/2001/sw/BestPractices/XSCH/xsch-sw/

making a few minor changes and adding quite a few todos (in red italics, 
class="todo")
which indicate what I am now working on. I will continue on this today 
and tomorrow.

The aims of the changes are:
- to turn the document from a discussion of possible practices into a 
description of best practice
- to leave the two options open on equality

If you have time to glance at the todos you may want to stop me before I 
get going on some of them!

Section 3 bears the brunt of the changes.

Jeremy