Object Storage backend
In order to sustain growth of instances, not having to do mega-replication of GBytes of assets and help #64 (closed), having to ability to use a object storage for attachments can be really interesting.
Use S3 api as an attachments storage
Use Swift api as an attachments storage
Use B2 api as an attachments storage
Option to have a pleroma-managed cache of attachments, like use 10 GByte for lastest attachments locally to not use the upload bandwidth (not cheap in general) of thoses services.