Modify aiscript

Added a stalker type AI to the AIScript
Added Archetype class to AIScript
Stalker leashes if player gets too far away
Other mobs stop animating if player gets too far away

Bug: In aiScript the transform.position is based on the Prefab not on the tiled placement, need to find a workaround for this
Testing: Find a good distance for both stalker leashing and wanderer stopping