exclude devise validatable module?

[salmanasiddiqui]

Devise token auth overrides email_required? and email_changed? methods just to disable devise validations. Overriding email_required? seems ok as its a method defined by devise so people can expect devise token auth to override it. But overriding email_changed? is not the cleanest way to disable validations. I wanted to use it in condition for callbacks but ended up using email_change after coming to know that email_changed? is overridden by devise token auth

As devise suggests itself, that if there is a need to modify devise validations, then its better to just implement your own validators and exclude validatable module.

[zachfeldman]

Closed in favor of #662 (just to consolidate)