Draft: Hunger system

Adds an (as of yet incomplete) hunger system. Hunger increases over time. Once hunger is over 70% movement speed and max health decrease linearly down to 70% as hunger goes to 100%. There is no additional penalty at 100% hunger. To test this, turn off SCT as it will bug out. The UI is very much still a draft. Hunger is right below max energy and above combat rating in the bag window (it has the same icon as energy but a % sign after the number). The debuff icon currently uses the crippled debuff icon and the health bar that is limited goes purple like when you are cursed. NPCs don't react to hunger yet either, though this won't matter too much if you keep on moving. Food decreases hunger but potions do not. Cactus Colada and Sunflower Iced Tea become the new meta. It becomes important to stock up on supplies before raiding a dungeon.