Use-own-generator per-world

[TheWranger]

Is your feature request related to a problem? Please describe.
People who want to modify the world generation in the overworld to add a seafloor cannot do so without removing BentoBox's world generation for the nether.

Describe the solution you'd like
The ability to toggle use-own-generator for each world instead of only being able to turn it on for all of them at once.

Additional context
I came here from AcidIsland with the assumption that BSkyblock also has the use-own-generator configuration option, sorry if this in the wrong section.

[TheWranger]

Rewrote ticket for better context

[tastybento]

BentoBox doesn't actually do the generation, the individual Addon does. So if you'd like the ability for AcidIsland to do this it's best to move it to the AcidIsland list. Also, do you just want a sea floor option? Or do you really need to use your own generator?

[TheWranger]

Just the ability to use our own generator, then we can make our own sea floor.