Pairing attempt fails
It looks like everything is running right. I can see Homebridge in the Home app on iOS. The Homebridge server shows all of Smartthings devices being registered. But every time I try to actually pair them it says "Couldn't add Homebridge."

Here's the output from running DEBUG:

```
  EventedHTTPServer Server listening on port 51826 +0ms
[10/28/2016, 11:16:13 PM] Homebridge is running on port 51826.
  EventedHTTPServer [::ffff:192.168.1.10] New connection from client +22s
  EventedHTTPServer [::ffff:192.168.1.10] HTTP server listening on port 38641 +21ms
  EventedHTTPServer [::ffff:192.168.1.10] HTTP request: /pair-setup +114ms
  HAPServer [CC:22:3D:E3:CE:30] HAP Request: POST /pair-setup +8ms
  HAPServer [CC:22:3D:E3:CE:30] Pair step 1/5 +38ms
  EventedHTTPServer [::ffff:192.168.1.10] HTTP Response is finished +515ms
  EventedHTTPServer [::ffff:192.168.1.10] HTTP request: /pair-setup +8s
  HAPServer [CC:22:3D:E3:CE:30] HAP Request: POST /pair-setup +4ms
  HAPServer [CC:22:3D:E3:CE:30] Pair step 2/5 +12ms
  EventedHTTPServer [::ffff:192.168.1.10] HTTP Response is finished +335ms
  EventedHTTPServer [::ffff:192.168.1.10] HTTP request: /pair-setup +148ms
  HAPServer [CC:22:3D:E3:CE:30] HAP Request: POST /pair-setup +3ms
  HAPServer [CC:22:3D:E3:CE:30] Pair step 3/5 +10ms
  HAPServer [CC:22:3D:E3:CE:30] Pair step 4/5 +137ms
  HAPServer [CC:22:3D:E3:CE:30] Pair step 5/5 +18ms
  Accessory [Homebridge] Paired with client 810A7AF1-7476-4382-B7EB-0965868235F9 +30ms
  EventedHTTPServer [::ffff:192.168.1.10] HTTP Response is finished +29ms
  EventedHTTPServer [::ffff:192.168.1.10] Client connection closed +148ms
  EventedHTTPServer [::ffff:192.168.1.10] New connection from client +27ms
  EventedHTTPServer [::ffff:192.168.1.10] HTTP server listening on port 38757 +8ms
  EventedHTTPServer [::ffff:192.168.1.10] HTTP connection was closed +64ms
  EventedHTTPServer [::ffff:192.168.1.10] HTTP server was closed +8ms
  EventedHTTPServer [::ffff:192.168.1.10] HTTP request: /pair-verify +22ms
  HAPServer [CC:22:3D:E3:CE:30] HAP Request: POST /pair-verify +3ms
  HAPServer [CC:22:3D:E3:CE:30] Pair verify step 1/2 +15ms
  EventedHTTPServer [::ffff:192.168.1.10] HTTP Response is finished +63ms
  EventedHTTPServer [::ffff:192.168.1.10] HTTP request: /pair-verify +172ms
  HAPServer [CC:22:3D:E3:CE:30] HAP Request: POST /pair-verify +3ms
  HAPServer [CC:22:3D:E3:CE:30] Pair verify step 2/2 +14ms
  HAPServer [CC:22:3D:E3:CE:30] Client 810A7AF1-7476-4382-B7EB-0965868235F9 verification complete +20ms
  EventedHTTPServer [::ffff:192.168.1.10] HTTP Response is finished +12ms
  EventedHTTPServer [::ffff:192.168.1.10] HTTP request: /accessories +110ms
  HAPServer [CC:22:3D:E3:CE:30] HAP Request: GET /accessories +3ms
  EventedHTTPServer [::ffff:192.168.1.10] HTTP Response is finished +127ms
  EventedHTTPServer [::ffff:192.168.1.10] HTTP request: /pairings +2s
  HAPServer [CC:22:3D:E3:CE:30] HAP Request: POST /pairings +5ms
  HAPServer [CC:22:3D:E3:CE:30] Removing pairing info for client +22ms
  Accessory [Homebridge] Unpairing with client 810A7AF1-7476-4382-B7EB-0965868235F9 +6ms
  EventedHTTPServer [::ffff:192.168.1.10] HTTP Response is finished +24ms
  EventedHTTPServer [::ffff:192.168.1.10] Client connection closed +93ms
  EventedHTTPServer [::ffff:192.168.1.10] HTTP connection was closed +14ms
  EventedHTTPServer [::ffff:192.168.1.10] HTTP server was closed +5ms
```

Any ideas?
