An undo option for network edits

[GoogleCodeExporter]

What steps will reproduce the problem?
1. Create a random network. 
2. Delete some random modules from the network. 
3. Try to undo the delete.  

What is the expected output? What do you see instead?
I would expect to see the deleted modules appearing back with the same 
connections if I undo the delete.  I dont see an undo option.

What version of the product are you using? On what operating system?
DeVIDE-re-v.9.8.3784 on Linux. 

Please provide any additional information below.

Original issue reported on code.google.com by [email protected] on 12 Aug 2010 at 9:39