def with_translations(*locales)
      locales = translated_locales if locales.empty?
      where :translations.matches => {:locale => {"$in" => locales.flatten}}.merge(required_fields_criteria)
    end
def with_translations(*locales)
      locales = translated_locales if locales.empty?
      where :translations.matches => {:locale => {"$in" => locales.flatten}}.merge(required_fields_criteria)
    end
Finds documents where translations for given locales are present and where
 attributes with presence validations aren't nil
 Params String or Symbol or Array of Strings or Symbols
 Returns Mongoid::Criteria