Zurku Gravestones

Update for **Hytale Server 0.7.0**.

### What changed
- Ported block and chunk handling to the new 0.7.0 API. `World.getChunkIfLoaded`, `World.getChunkAsync`, `WorldChunk.setBlock` and `WorldChunk.getBlockType` no longer exist, so blocks are now written via `BlockOperations.setBlock` and read via `SectionReader`.
- Added helper methods in `BlockStateUtil` (`setBlock`, `setBlockNow`, `clearBlock`, `getBlockType`). Placing and removing gravestones now runs on the world thread.
- The plugin now requires Hytale Server 0.7.0 or newer (updated `ServerVersion` in `manifest.json`).

### What did not change
- No gameplay or feature changes. Gravestone spawning, collecting, breaking, access rules and settings work as before.

### Compatibility
- Requires **Hytale Server 0.7.0 or newer**.
- Does **not** work on 0.6.x, because it uses the new 0.7.0 API. Use release 1.2.0 for older servers.

### Known notes
- The server logs `Unused key(s) in 'Furniture_Zurku_Gravestone': Flags.IsUsable`. The flag was removed in 0.7.0. It is only a warning and has no effect on functionality.

Fork of Zurku Gravestones.