Custom category with same name transfers entities

[mpigsley]

Expected behavior

If a category with the same name exists on an entity and that same category is created on a new entity, it should create a brand new blank category rather than just moving the old category to the new entity.

Actual behavior

Okay, this is weird. I have a stats category that I added to creatures a long while ago. I went to go add a stats category to characters and it removed it from creatures but it was added to characters with all the existing attributes from creatures.

Steps to reproduce the behavior

Create a Stats category with some custom attributes. Go to add a Stats category to a new entity. The new category should exist with the existing attributes but the old category will be gone.