curl -i -X POST 'http://localhost:3080/v2/shutdown' -d '{}'

POST /v2/shutdown HTTP/1.1
{}


HTTP/1.1 201
Connection: close
Content-Length: 0
Content-Type: application/octet-stream
Date: Thu, 14 Jun 2018 08:35:18 GMT
Server: Python/3.5 GNS3/2.1.8dev1
X-Route: /v2/shutdown

