Sure.

I ended up refactoring how error messages in this `ViewSet` are [stored](https://github.com/chuckharmston/zamboni/commit/d4bf62e724c1ad7c2b5aa4df3388dae4d91fdbde#L3R29) and [served](https://github.com/chuckharmston/zamboni/commit/d4bf62e724c1ad7c2b5aa4df3388dae4d91fdbde#L3R63). This allowed me to [test the response body](https://github.com/chuckharmston/zamboni/commit/d4bf62e724c1ad7c2b5aa4df3388dae4d91fdbde#L2R101) to ensure that the correct messages are being served. Seems good.

Thanks!