Make use of WorldUnloadEvent for plugin that calls Bukkit.getServer().unloadWorld(World world)

In my plugin, I unload and delete, and create a new fresh world. The problem I Irealized is, that when I preform this with a world with same name, structure will not grow and will be plain land with weird biome map. To fix this, I decided to do what this commit does with my on Plugin. Although this has temporary fixed issue, but it would be really nice if this was implemented in TerrainControl.

Note: I edited two file just to follow the format of onWorldInit.