E&S CVS Commit: Trellis - Simplified rollback support for collections. Only changes

[pje at eby-sarna.com]

Author: pje
Date: Fri Dec 28 14:26:41 2007
New Revision: 2449

URL: http://svn.eby-sarna.com?rev=2449&view=rev
Log:
Simplified rollback support for collections.  Only changes
done to non-"future" cells need to be undo-logged, and the
entire structure will be rolled back to the first point of
change when *any* change to the structure is rolled back.

Modified:
    Trellis/peak/events/collections.py
    Trellis/peak/events/trellis.py
    Trellis/test_trellis.py