Fails if you have 'Lux' bulbs in the network - non-color-changing ones

[mahood73]

The script assumes all lamps can handle the 'xy' color setting, but in my home I have a couple of Lux bulbs which are just white.

As such I get this error:

Setting lights to 0,50,199
node_modules/thebutton-hue/node_modules/node-hue-api/node_modules/q/q.js:126
throw e;
^
Api Error: parameter, xy, not available

The Hue API you're using does return the lamp information, so I added a couple of conditionals:

if(lights.lights[i].type=="Extended color light")

(Lux lamps return 'Dimmable light' by contrast).

Once I work out how, I'll do a pull request :)