* Don't fail on urls that don't contain the project id (direct image urls).
* Don't fail when the work is deleted.
* Parse artist name from url when possible. This way the artist finder works on bad_artstation_id posts.
* Set canonical source url to `https://artist.artstation.com/projects/12345` instead of
`https://www.artstation.com/artwork/1235` (this way we preserve the artist name).
* Cache api call.
* Include api call results in /source.json.