[relax-ng] New draft

I have put a new draft at:

  http://www.thaiopensource.com/relaxng/spec.html

This includes the proposed restrictions on attribute wildcards and 
interleave.  See sections 7.3 and 7.4.  I have also added a note to section 
4.9 and to section 7.1.4.

I haven't spell-checked it yet, but apart from that I think it's finished.

James