Riscoss 1.1.0 - Parent/children list not updated

[anicolo66]

In Riscoss 1.1.0, if an Entity is added as Parent, and another one is added as Children of another Entity, the list of remaining Entities is not updated, then the Entities already added remain in the list, both in Parent and in Children.
If an Entity is added, at least after pressing Save, it should be removed from the list of next Entities to add.