- API {farming.register_hoe(), farming.register_plant()}
- Fertilities -> Plant only grow on soil with a fitting fertility, e.g. Wheat only grows on grassland, while cotton grows in deserts and grassland)
- New soil: Desert Sand
- Place seeds instead of plants

This adds protection for furnaces (when the area is protected, so it the
furnace).
Also made the codes a bit shorter..

These changes allow players to punch up old bones or their own.
If there is no area for bones, drop the items instead of delete.
Notify the player where he died, so he can find them again.

Stair recipe now outputs six stairs rather than four.

Also, move "waving = 1" property for grasses/shrubs over to default/nodes.lua
and put all instances of this property right under the drawtype, since they
are directly related and depend on the above.