Do whatever you want to do with this code.
Literally the only restriction is if you change the wording of the license, you cannot still call it the WTFPL.

Make a fork, make changes, submit a pull request, and I (Morlok8k) will review it and we go from there.
If you want to do something else, do it - but this project (https://github.com/Morlok8k/MinecraftLandGenerator/) won't be updated with your code.

- Morlok8k