By default, the `phue` library will store the file containing the token
and the bridge configuration under `~/.python_hue`.
That's outside of our application folder, and it can't easily be copied
around or added to Docker volumes.
We should instead have it under `<WORKDIR>/light.hue/config.json`, in
line with what the other plugins do, and if `~/.python_hue` is available
but `<WORKDIR>/light.hue/config.json` isn't then we should copy the
legacy file to the new one.
continuous-integration/drone/push Build is passingDetails
I've tried my best to keep it around, but the endpoints seem to be
broken, they no longer have a link to their API v3 documentation, and
the API Explorer that was supposed to be in the dashboard is gone.