modifications to CDT triangulation package

[Seth Teller <teller@csail.mit.edu>]

vitaliy,

if i remember correctly, you made some modifications
to CDT to enable editing a triangulation after it
was created -- is that right?  if so, can you
describe what operations (deletion, etc.) the new
package supports?

we are thinking about how to reorganize the pipeline,
with a (possibly mutable) CDT as a fundamental piece.

thanks,

seth

ps note:  replies set to bmg.