Handle host vs discovered IP

[TwitchBronBron]

If user specified host as some alphanumeric value (like my-roku-ultra), there's an underlying IP address also associated with that.

We should store both host and IP address as props on our device object.

If hostname doesn't resolve, but we have serialNumber specified, and then we also do network discovery and find a different ip address/hostname with that serialNumber, then THAT info should become the configured device and the discovered device is merged into that configured device (in memory only, for this session).

Could work out more details later, but this is the rough idea.