Tracker server should prune old torrents and swarm #164
Description
Quoting @DiegoRBaquero on #160 (comment)
Each swarm has an LRU cache which in some case might never remove peers, consuming RAM. OpenWebTorrent trackers, who's been running without restarting for the longest shows us this, it's full of peers who left ungracefully: https://tracker.openwebtorrent.com/stats
To fix this, we could implement caching torrents on server to prune old torrents and their swarm to limit memory consumption.
What do you think?