Add an option to raise the floor portal #43
Description
It would be nice if you could set the floor to a different height. I have found not having this annoying because it means I can not make an overworld without access to the ground.
Something like the ceiling portal lowering but it enables you to move the floor up.
I can see that you can flip the dim by setting the dim_celing to a negative number but it just becomes the ceiling which I can see being useful on the end dimensions but it doesn't allow you to raise the floor
If this is a difficult thing to do, don't worry about it, I think I can get around it but it would be nice and I think other people might find it useful as well.