Store description of an artwork
Test adding description through private API
Store artwork config
Wrap routes in standard middleware
Tidy up private API routes

User id is a thing that might not exist and doesn't at the moment for
inspiration (might change). I've removed this from the URLs and have
allowed it to be passed through as a query parameter.
get-or-create-user should not fail on nil
Add mime_type to artwork
Receive files and upload to s3 rather than link

Previously gallery just stored urls to media, we want to take control of
the media so it is not sent to gallery adn then stored in s3