Improved zombie AI. Zombies now have eyes and can see humans. Zombies have two states, idle and enraged. In idle state they shuffle around randomly and have short range vision. If a human comes into range there is a short alert period (not yet graphically shown) in which the human could retreat from. Otherwise the zombie becomes enraged and chases the player. Enraged zombies can see further.
Initial implementation of day/night cycle and player flashlight. Day/night cycle is current very fast for testing (10 minutes advances per turn, only 144 turns per day). Darkness limits the player's view distance.