Feature Request: Add branching logic to config

[dbudwin]

It would be great if config.py supported more of a tree-like structure than a linear structure.

For example, I have a trait that is 50/50 in terms of rarity. Depending on which one of the two options is selected, I want to add different traits on top of it.

For reference, https://nft-generator.art/app supports a similar capability.

A way this could be implemented in the config.py would be to add 2 keys named: next_trait_id and next_trait_rarity. next_trait would be a field that takes the id of the trait to follow and next_trait_rarity represents the odds that the trait will be applied.