Improve performance on update/delete

MyCoRe's update/delete system doesn't act very clever. Things that should done one time, are done multiple times over and over.

Example:

• A user delete's a parent object with 500 children.
• MyCoRe tries to delete the parent, but first, it has to delete all children.
• MyCoRe runs through each child and deletes it.
• BUT after the deletion of ONE child, the parent object will be updated.
• This results in updating the parent 500 times, before its actually deleted.