change email field

[Matthew Turney]

I see that Devise can be configured to use a different field for authentication, but can I also change the expectation that my model must have an email property? I am working with an existing database and the users table uses the field `login` for both email and authentication. It is not an option to migrate this to a different named field. Is there a way to remap the `login` field to `email` in the model or otherwise convince Devise to use login in place of email?