When a value doesn't change don't create an undo operation
Submitted by Alvaro del Castillo
Link to original bug (#144733)
Description
We need to check in every operation with undo support if it really has created some change in planner and if not, don't create un undo operation for it.
For example, when you add a new resource the name field is selected to be in edition mode. If you don't change the name field, you finally has 2 undo operations: insert resource and edit name resource. But you haven't change the edit name resource, so it is confussing.
When you have several undo commands with no changes, it is very confussing to undo operations. It seems like if the undo system have a delay.