Feature request: Option to allow cave biomes to spawn in any overworld biome.

[slidedrum]

I would love the option to be able to allow a desert cave to spawn under an ocean, or a prismarine cave to spawn under a jungle. I know it doesn't make a whole lot of sense, but that's how I would like to play.

Would be nice to specify what caves can spawn in what biomes for people who want to customize it like that. Even if I would allow any cave in any biome.

Also, an option to disable flooded caves in ocean biomes. It can create some very nasty looking chunk borders and can look really bad with other cave gen mods.

And one last thing, while it would be great to have the option for cave biomes to spawn under Y 0 for the new generation, but please let it be an option as I kind of like it the way it is right now where they only show up above Y 0. (not sure if these should be a separate issue as they are separate requests, but in the name of less clutter I'll put it here.)