ActiveRecord helper methods

[aaronmallen]

Elevator pitch, describe and sell us your feature request

As a developer,
I want to be able to use my ActiveRecord models as context classes
so that I don't need to create separate context classes for my interactors when the output is just going to be fed to a model anyway.

Is your feature request related to a problem

Have you considered any alternatives

Additional Comments

We should provide a helper method for ActiveRecord models, something like acts_as_context that would include ActiveInteractor::Context::Base status methods (i.e. #fail!, #called, etc...). This way we could call the contextualize_with method in a given interactor and set the value to one of our ActiveRecord model classes.