def options
      accepted_options.each_with_object({}) do |option_name, options|
        option_value         = send(option_name)
        options[option_name] = option_value unless option_value.nil?
      end
    end
def options
      accepted_options.each_with_object({}) do |option_name, options|
        option_value         = send(option_name)
        options[option_name] = option_value unless option_value.nil?
      end
    end
Returns default options hash for a given attribute class

 @example
   Virtus::Attribute::String.options
   # => {:primitive => String}

 @return [Hash]
   a hash of default option values

 @api public