def remove_all(*classes)
      classes.flatten!
      if classes.empty?
        @deletes += 1
        indexer.remove_all
      else
        @deletes += classes.length
        classes.each { |clazz| indexer.remove_all(clazz) }
      end
    end
def remove_all(*classes)
      classes.flatten!
      if classes.empty?
        @deletes += 1
        indexer.remove_all
      else
        @deletes += classes.length
        classes.each { |clazz| indexer.remove_all(clazz) }
      end
    end
See Sunspot.remove_all