Checking persistence in view is "leaky"

[jwright]

Checking if the model is "persisted" in the limits form has several downsides.

1. It requires an instance of a model and can't work on just class names
2. It requires the addition of another variable (model vs. form.object)
3. It seems like that should not be checked in the view as it will then need to be checked in other places

It feels like it should be part of the limiter (pass in an instance or a class and the limiter will determine).

In addition, it seems like some additional checks within certain workflows should be checked and ignored in other workflows. (e.g. in this controller action we need to check if the model is persisted, in another one, we don't need to).