More information on using the HTML 4.0 tables in XML spec DTD

Here are the following things I've done to incorporate the HTML 4.0 table
model into the XML spec DTD:

- Lowercased all markup names
- Changed %inline; to (%p.pcd.mix;)*
- Removed OMITTAG flags
- Removed all semantic-information comments
- Made "cosmetic" DTD changes to be XML compliant
- Changed %flow; to (%p.pcd.mix;|%p.mix;)*
- "Resolved" attribute declared-type entities 
- Change uses of NUMBER to NMTOKEN
- Removed HTML common %attrs; attributes
- Removed HTML %reserved; attributes
- Removed HTML datapagesize attribute

Other than removal of a few attributes that don't seem relevant to
non-presentational specification authoring, and the substitution of cell
contents that are compatible with the main DTD, the markup model should be
identical to the original.

Unless I hear from folks soon (e.g., "I desperately need attribute xyz"),
this is going to constitute the HTML 4.0 table support in the DTD.

I've attached the fragment for your review.  I haven't incorporated or
tested it yet, but if you happen to notice anything amiss with it, let me
know.

	Eve