Code review comment for lp://staging/~michael.nelson/ubuntu-webcatalog/1002262-dont-insert-errors-via-ajax

I've just pushed up some further changes that:

1) Ensures that if in the future, the reviews view 500's for some other reason, we won't display the result, and
2) Ensures that if in the future, the rnr api does return an error, we catch it rather than also erroring.