Tootsuite/mastodon Issue#1847: Media content caching strategy

People are currently discussing about the legal implications of storing images coming from federated Mastodon instances. A lot of this stems from an influx of users at pawoo.net, a Mastodon instance set up by Pixiv, posting CP and CP-like content. While Pixiv explains that these images are legal in Japan where the servers are hosted, a lot of the instances federated with pawoo have jurisdictions setting such images as illegal, or at least immoral. As response, a lot of instances have defederated from pawoo.