Issue Description:

Nether only generates in vanilla Hell biome type

Steps to reproduce:

1. Go to the Nether

Additional Information:

• fml-client-latest.log or fml-server-latest.log:
• Screenshots:

Affected Versions (Exact numbers, do not use "latest"):

• Biomes O' Plenty: 4.0.1.2006
• Minecraft: 1.9
• Forge: 1868

EDIT: I just realized that isn't the latest version. Curse has been downloading old versions for me for some reason, trying with updated BoP.

They haven't been re-added yet

See: #746