[BUG] Home Control buttons  : all home devices are exposed
First - THANK YOU for adding the Home Control buttons!  I know that was a lot of work, and I really appreciate it!  I tried it this morning, and ran into an interesting bug.  When I enabled it (code below), all of my Lutron Caseta and Philips Hue accessories showed up as additional Homebridge accessories.  They still exist as native HomeKit accessories as they are supposed to, but are now duplicated through Homebridge.

```
  {
    "platform": "HarmonyHubWebSocket",
    "name": "FamilyRoomHarmonyHub",
    "hubIP": "192.168.1.228",
    "showTurnOffActivity" : false,
    "publishHomeControlButtons" : true
  },
```

![image](https://user-images.githubusercontent.com/46855061/54996361-7900ca00-4f9f-11e9-9636-f6b1859a9f17.png)
