Updates to StateController, Created NPC1Health class

Added attacking code to StateController, modified gem search so that
NPC1 will stop attacking and go after a gem if its life is below 4
points. (Try changing health meter in inspector), gems will add 1 to
NPC1 health. I also added code to damage NPC1 when colliding with "Ammo"
but it caused him to do damage to himself whenever he tried to attack.
That code is commented out in NPC1Health script. Please take a look at
all my changes.