Core/Units: refactor rage generation to reflect patch 4.0.1 changes:

* melee attacks will now send their awarded rage within SMSG_ATTACKER_STATE_UPDATE and moved the rage reward mechnic from Unit::DealDamage into Unit::AttackerStateUpdate

* killed CleanDamage struct and provide plain unmitigated damage values instead as since patch 4.0.1 the rage gained from damage taken is fully normalized and ignores any kind of damage reduction or negation

src/server/game/Entities/Player/Player.cpp

@@ -710,7 +710,7 @@ uint32 Player::EnvironmentalDamage(EnviromentalDamage type, uint32 damage)
     environmentalDamageLog.Resisted = resist;
     SendMessageToSet(environmentalDamageLog.Write(), true);
 
-    uint32 final_damage = Unit::DealDamage(this, this, damage, nullptr, SELF_DAMAGE, SPELL_SCHOOL_MASK_NORMAL, nullptr, false);
+    uint32 final_damage = Unit::DealDamage(this, this, damage, 0, SELF_DAMAGE, SPELL_SCHOOL_MASK_NORMAL, nullptr, false);
 
     if (!IsAlive())
     {