Add command to purge old inventory data

[orkun1675]

This plugin creates tons of files. The file count for multi-inv has gone over 100k on my server. This slows down the server and causes problems during backups. We really need a cleanup code. Delete all data of the players who have not logged in for 21 days. Please implant this asap.

/mv inv purge

Thanks!

[Portanna]

Any progress on this?

[dumptruckman]

It's not going to be soon. See my response in #320 about something you can do till then.