Startup Issue
Hi, Since the most recent update homebridge is no longer starting up and I'm seeing the following error (its reversed) and seems related to the harmonyhub plugin:

```
8-01-11 08:48:53 | stdout | at Function.Module._load (module.js:491:3)
-- | -- | --
2018-01-11 08:48:53 | stdout | at tryModuleLoad (module.js:499:12)
2018-01-11 08:48:53 | stdout | at Module.load (module.js:556:32)
2018-01-11 08:48:53 | stdout | at Object.Module._extensions..js (module.js:654:10)
2018-01-11 08:48:53 | stdout | at Module._compile (module.js:643:30)
2018-01-11 08:48:53 | stdout | at Object.<anonymous> (/homebridge/node_modules/node-xmpp-core/lib/Stanza.js:4:15)
2018-01-11 08:48:53 | stdout | at require (internal/module.js:11:18)
2018-01-11 08:48:53 | stdout | at Module.require (module.js:587:17)
2018-01-11 08:48:53 | stdout | at Function.Module._load (module.js:468:25)
2018-01-11 08:48:53 | stdout | at Function.Module._resolveFilename (module.js:538:15)
2018-01-11 08:48:53 | stdout | Error: Cannot find module 'ltx/lib/Element'
2018-01-11 08:48:53 | stdout |  
2018-01-11 08:48:53 | stdout | ^
2018-01-11 08:48:53 | stdout | throw err;
2018-01-11 08:48:53 | stdout | module.js:540
2018-01-11 08:48:53 | stdout | [2018-1-11 08:48:53] Loaded plugin: homebridge-harmonyhub
2018-01-11 08:48:53 | stdout | [2018-1-11 08:48:53] ---
2018-01-11 08:48:53 | stdout | [2018-1-11 08:48:53] Registering platform 'homebridge-flic.Flic'
2018-01-11 08:48:53 | stdout | [2018-1-11 08:48:53] Loaded plugin: homebridge-flic
2018-01-11 08:48:53 | stdout | [2018-1-11 08:48:53] ---
2018-01-11 08:48:53 | stdout | [2018-1-11 08:48:53] Registering platform 'homebridge-edomoticz.eDomoticz'
2018-01-11 08:48:53 | stdout | [2018-1-11 08:48:53] Loaded plugin: homebridge-edomoticz
2018-01-11 08:48:53 | stdout | └───────────────────────────────────────────────────┘
2018-01-11 08:48:53 | stdout | │ sudo chown -R $USER:$(id -gn $USER) /root/.config │
2018-01-11 08:48:53 | stdout | │       to the local update config store via        │
2018-01-11 08:48:53 | stdout | │        Try running with sudo or get access        │
2018-01-11 08:48:53 | stdout | │              npm update check failed              │
```

I did have issues with harmonyhub plugin when i updated npm on a local install which is why I switched to your docker, any ideas?