defaults don't work with scopes

[amiel]

Assuming the example configuration:

  class User < ActiveRecord::Base
    has_bitmask_attributes :notifications do |config|
      config.attribute :send_weekly_newsletter,    0b0001
      config.attribute :send_monthly_newsletter,   0b0010, true
    end
  end

A new user will not match User.with_notifications(:send_monthly_newsletter), until something on the mask is set and saved.

Probably defaults should be set after_initialize so that the defaults are actually saved to the database.