$ curl  -i -X OPTIONS http://localhost:4567/
 HTTP/1.1 204 No Content
 Allow: HEAD,GET,POST,DELETE,OPTIONS
 X-Content-Type-Options: nosniff
 Server: WEBrick/1.3.1 (Ruby/2.3.3/2016-11-21)
 Date: Thu, 30 Mar 2017 19:11:56 GMT
 Connection: Keep-Alive
 $