Snapshots are leaking tile entity data through to world save

The bug

Snapshots are loading and saving tile entity data for tile entities that have been destroyed.

How to reproduce

1. Create flat world with no structures or other entities (optional - for ease of debugging)

2. Place redstone comparator

3. Destroy redstone comparator

4. Stop server

5. Tile entity for redstone comparator is still saved to the world

This also occurs for at least bed tiles as well. It does not occur for skulls. Other tiles have not been tested.