#231 Artist images not being fetched properly

[Anonymous]

Due to a change in Last.fm API, fetching artist images from Last.fm no longer functions. Every request returns a blank grey image with a white star. It would be good to use a different service for getting artist images; as it stands, I now can use the Subsonic API for everything in my app except for artist images. While not the end of the world, it is a slight nuisance.