Removed smelting XP percentage option

Caused crashes on load server side
Fixed crash caused by option to remove XP bar

Caused crashes client side
Changed default items dropped on death lifespan

Made it so items dropped when a player dies will not despawn for a very
long time
Round long numbers before printing them to HUD
Simplified player jumping check
Reduced speed calculations on non player entities
Changed hardness code into Forge event
Added options to hide various HUD elements
Fixed client side crash in SMP when XP bar hidden
Really fixed the client side crash this time
Creative mode text option and HUD improvements

Creative mode text is helpful when certain HUD features are hidden
When the hotbar is hidden, other HUD features move down
Another small HUD improvement
No movement penalty when jumping