Renaming a widget breaks its associated references in bindings

[jdaignault]

Renaming a widget breaks its associated references in bindings, forcing the user to manually repair all the bindings that were referencing it.

Steps to reproduce:

1. Create a widget with an Image
2. Create a binding with a Read a Property node for the Image
3. Connect its output to a Call a Function destination node, and set its function to Set Visibility
4. Rename the Image to a different name, and recompile the blueprint
5. Observe that the binding now contains an error, and that its nodes still reference it by its previous name