Option for changing enchant rules in world creation.

What I mean by this is for players to be allowed to limit the kind of enchantments you can get in the world, and also which enchantments are considered "treasure."

For example...

 I could make a world that doesn't allow enchantments at all.
 I could remove the Fortune enchant from the world so that resources are more limited.
 I could make a world where you couldn't combine enchantments to level them up.
 I could make a world where the enchantment levels were higher or lower than normal, and/or make enchants past a certain level be considered "treasure," and thus normally unobtainable.

...and this would all be decided on the individual level for each enchantment.