Fast enough worldgen can cause infinite loops & StackOverflowError

[ghost]

https://pastebin.com/suYDm4gt

reported here after little conversation: https://www.reddit.com/r/feedthebeast/comments/7ownfq/chunk_pregenerator_v16_is_now_out_now_with/dskhfy1/?context=3

[mura3277]

Unsure if this would still be relevant if/when the ore gen refactor finally gets merged.

@nekoexmachina Do you know what version of GT you were using?