Tags

I created two models, topics and tags, and wrote tests for each model. I associated these models with story and then added a 'tags' field to the story representer. I'm not sure about the tags method on story -- for representer purposes, it seems like we're only interested in the names, but should the method return the whole object?
they should be unique anyway because of the uniqueness constraint on the topic and tone models, but I could add sort