Harmony offline from Wifi - homebridge crashes
**Describe the bug**
Harmony was offline, however, the entire homebridge crashed upon start up - see logs


**To Reproduce**
Disconnect Harmony Hub from Wifi


**Expected behavior**
Error handling would have detected this, but allowed the rest of the homebridge to proceed

**Screenshots**
See Logs above

**IOS (please complete the following information):**
IOS 14

**Logs**
[9/19/2020, 4:51:05 PM] TypeError: Cannot read property 'length' of undefined
    at HarmonyBase.checkHubsFound (/usr/local/lib/node_modules/homebridge-harmony/harmonyBase.js:126:24)
    at HarmonyPlatform.<anonymous> (/usr/local/lib/node_modules/homebridge-harmony/harmonyBase.js:227:16)
    at HarmonyPlatform.emit (events.js:315:20)
    at Timeout._onTimeout (/usr/local/lib/node_modules/homebridge-harmony/harmonyPlatform.js:168:16)
    at listOnTimeout (internal/timers.js:549:17)
    at processTimers (internal/timers.js:492:7)

**Config**
        {
            "platform": "HarmonyHubWebSocket",
            "name": "Bridge"
        },

**Additional context**
Can you modify the exception handling so it doesn't cause a complete crash of the homebridge
