[Bf-python] DAG/display lists

[Ken Hughes]

So what's the recommended API way to handle DAG updates from a script?
Should each type that changes data have an update method?

A related curious thing: I've noticed that if I modify a mesh from a 
script, and the mesh is visible in a 3D window, the changes will appear 
when the script finishes as long as the mode is not Object Mode (and of 
course, not Edit Mode).  I don't need to do anything special for this 
(no calls to DAG code); it just updates.

Ken