Experimental dimming support

try dimming adding a device with an on url of something like:

http://192.168.1.201:3480/data_request?id=action&output_format=json&serviceId=urn:upnp-org:serviceId:Dimming1&action=SetLoadLevelTarget&DeviceNum=<deviceid>&newLoadlevelTarget=${intensity.percent}

dont forget to replace deviceid, clear devices, and rediscover