Clean up list of services
The current list of services includes some that haven't been popular for quite some time and we don't really use in apps anymore. Some of them are also problematic from a PR point of view because of that company's business practices, and having them visible in Settings by default reflects badly on us because it looks as though we're associated with them.
I'd be interested in revisiting which of these are still used and which we could remove, but I think the following ones we could probably get rid of quite easily:
- Flickr
- Foursquare
- Last.fm