Revert "Removed vanilla world types"
Fixed buggy alcohol poisoning death. Added custom death message for alcohol poisoning and heat stroke.
Merge pull request #691 from Deadrik/revert-688-fixDisableVanillaWorldTypes

Revert "Removed vanilla world types" due to server crash.
Items that implement IFluidContainerItem can be used with barrels and large vessels now.

This will add support for fluid item containers that are not in the
simple forge FluidContainerRegistry, but instead use the
IFluidContainerItem interface.
avoid vanilla MC from creating new snow if already some there
- renamed some variables, removed unused variables.
- equalized number of layers: minimum is zero (1 layer), maximum is 7 (8 layers)
- always mask meta wiht 7 (meta & 7)
- restructured updateTick() so it is (hopefully) easier to understand

Still open:
- speed reduction is a bit digital:
  1 layer = no speed lost;
  2 layers = 2% slower;
  3 or more = 42% less speed
- canAddSnowCheckNeighbors is not working very well IMHO:
  if I have a block (1 high) on a flat plain, snow will
  accumulate on its top, but not on its base
- Options to tweak generation speed