Can't get a stateful switch to work :(
**Describe the bug**
Can't get a stateful switch to work. The logs report invalid header token. I have a relay which works with REST APIs. simply by sending a get request like: 
http:/IP/on
http:/IP/off
http:/IP/state
http:/IP/toggle

Everyting works if doing from a browser or a command line. It also works if I use a stateless switch. But I need a stateful.

**Version** (output of `npm list -g homebridge homebridge-http-switch`)
 - homebridge: 4.6.3
 - homebridge-http-switch: 0.5.26

**Configuration**
```json
Your configuration goes in here
      {
          "accessory": "HTTP-SWITCH",
          "name": "Switch",
          
          "switchType": "stateful",
          
          "onUrl": "http://IP/on",
          "offUrl": "http://IP/off",
          
          "statusUrl": "http://IP/state"
        }  

**Additional context**
From logs:
[37m[2019-11-19 0:34:30][39m [36m[Switch][39m Error: Parse Error: Invalid header token
    at Socket.socketOnData (_http_client.js:456:22)
    at Socket.emit (events.js:210:5)
    at addChunk (_stream_readable.js:308:12)
    at readableAddChunk (_stream_readable.js:289:11)
    at Socket.Readable.push (_stream_readable.js:223:10)
    at TCP.onStreamRead (internal/stream_base_commons.js:182:23) {
  bytesParsed: 21,
  code: 'HPE_INVALID_HEADER_TOKEN',
  reason: 'Invalid header token',
  rawPacket: <Buffer 48 54 54 50 2f 31 2e 30 20 32 30 30 20 4f 4b 0d 0a 6c 77 49 50 2f 31 2e 34 2e 31 20 28 68 74 74 70 3a 2f 2f 73 61 76 61 6e 6e 61 68 2e 6e 6f 6e 67 6e ... 300 more bytes>
}