Tracked changes proposal

Hi

Here is my proposal for changes to the "Change Tracking in Text
Documents" section. I have included the decisions we made on the call
for completeness. 

1.
Remove the Open Office specific text:protection-key attribute from the
text:tracked-changes element. Open Office would presumably move this
information to an application specific area.

2.
Remove the text:merge-last-paragraph attribute from the
text:changed-region element. The behavior modified by this attribute
seems to be very specific to Open Office application. 

3.
I suggest we modify the office:change-info element as follows.

A. Remove chg-author, chg-date & chg-time attributes
B. Remove its text content
C. Allow office:change-info to contain any combination of the following
metadata elements: meta:generator, meta:creator, dc:date, dc:description
and meta:user-defined.

4.
After considering how to implement the text:format-change element it is
not clear to me how changes to styles, automatic-style and
style-properties would interact. Given the amount of work still
remaining on the specification it seems prudent to drop it or leave it
as is for this version of the specification. 

Talk to you at 1
-Phil