Subterranean-Waters

Adds a companion world gen features that creates large oceans, lakes, and biome border rivers under the overworld land mass.

Differences from Underground Ocean

• Does not generate in existing water biomes, configurable.
• Can be deactivated in biomes of your choosing.
• Reverted to the 1.7.10 code as the 1.11.2 code was really screwed up.