Add <Description> for Host device

[scottmwyant]

Probably a low priority item here but figured I'd submit it to get the concept logged.

I think it would make sense to have a <Description> element for the Host element. Attributes could be something like this:

<Device id="host" name="Host" uuid="someUUID">
    <Description manufacturer="MrIIoT" model="model" serialNumber="L99-{WAN MAC}" ></Description>
</Device>

This seems a little more elegant than including the serial in the "sender", which I think I suggested previously, though maybe that's appropriate too, not sure.