fix

1. change the storage to avoid multiplayer cannot store tomb data in a same location. (old storage json are still supported , but all new data will store player as a list)

feature

1. now tombstone will spawn on the surface of liquids even when players are diving under liquids (water, lava and etc)

Full Changelog: https://github.com/fly6516/SimpleTombStone/compare/1.20.4-Stable-1.0.3...1.20.4-Stable-1.0.4