The following constants were renamed:
ActiveModel::Serialization => ActiveModel::Serializable
ActiveModel::Serializers::JSON => ActiveModel::Serializable::JSON
ActiveModel::Serializers::Xml => ActiveModel::Serializable::XML
The main motivation for such a change is that `ActiveModel::Serializers::JSON`
was not actually a serializer, but a module that when included allows the target to be serializable to JSON.
With such changes, we were able to clean up the namespace to add true serializers as the ArraySerializer.
When you've got an AR Model and you override the `as_json` method,
you should be able to add default options to the renderer, like this:
class User < ActiveRecord::Base
def as_json(options = {})
super(options.merge(:except => [:password_digest]))
end
end
This was not possible before this commit. See the added test case.
