def search_on(column_source, methods)
      Array(methods).each do |method_name|
        join column_source
        self.searches += [{column_source: column_source.to_s, method_name: method_name.to_s}]
      end
    end
def search_on(column_source, methods)
      Array(methods).each do |method_name|
        join column_source
        self.searches += [{column_source: column_source.to_s, method_name: method_name.to_s}]
      end
    end
Allow user defined fields to sort on in addition to introspected fields