Fixed ghost AI, Minor changes to PointObject and MapManager

NOTE: Following tags needed in Unity: Cheese, GhostRed, GhostBlue,
GhostPink, GhostOrange.
Ghost release and AI fixed. Gamemanager now releasing ghosts after
correct timings/triggers. Mapmanager adding cheese tags to cheese.
PointObject incrementing cheesecount on gamemanager for ghost timing.