Add HandleRating EH to prevent AI from teamkilling you #151

Documenting for future usage
https://community.bistudio.com/wiki/addRating
https://community.bistudio.com/wiki/Arma_3:_Event_Handlers#HandleRating

Ratings are local to each player and when the rating dips below -2000, you become a valid target for 'Friendly AI'

When the rating gets below -2000, the unit's side switches to "ENEMY" (sideEnemy) and the unit is attacked by everyone.(see Rating Values)