def not_found(res, path)
      path = ::Rack::Utils.escape_html(path)
      res.status = 404
      res.write "<html><head></head><body><h1>File Not Found</h1><p>#{path}</p></body></html>"
      res.finish
    end
def not_found(res, path)
      path = ::Rack::Utils.escape_html(path)
      res.status = 404
      res.write "<html><head></head><body><h1>File Not Found</h1><p>#{path}</p></body></html>"
      res.finish
    end
Halt request and return 404