[implemented] Improve EVENT_ALLIANCE_POINT_UPDATE

[Ayantir]

EVENT_ALLIANCE_POINT_UPDATE (integer eventCode, number alliancePoints, boolean playSound, number difference, number reasonType)

reasonType =

1. ALLIANCE_POINTS_REASON_PLAYER = When you gain Alliance points by a gain on an ennemy player (killing participation)
2. ALLIANCE_POINTS_REASON_ATTACK_TICK = When you gain Alliance points by a gain on a attack Tick (you just captured a flag).
3. ALLIANCE_POINTS_REASON_DEFENSE_TICK = When you gain Alliance points by a gain on a defense tick (you just defended a flag).
4. ALLIANCE_POINTS_REASON_QUEST = When you gain Alliance points by validating a quest.

PS : ALLIANCE_POINTS_REASON_BATTLEGROUND_OBJECTIVE