- Modifications to `nether.is_player_in_nether()` and `nether.external_nether_teleport()`
- Renamed `players_in_nether[]` to `players_trapped_in_nether[]`
- Fixed punctuation in a comment. =D
Mapgen: Find a way to get the perlin noise values inside [-1; 1] or use
another noise.
The problem is visible in the nether forest, where the mapgen code flattens
the ceiling if it is very high.
Mapgen: Generate more detail inside the simple pyramid-like "buildings",
e.g. add a small treasure chest node which contains items