Core/Spells: Implemented battle pet experience related spell effects and auras

Port From (https://github.com/TrinityCore/TrinityCore/commit/9354b4ac8ec63f0b2ee5ceb3c8b6a3c6a75bd99f)

Source/Framework/Constants/AchievementConst.cs

@@ -637,9 +637,9 @@ namespace Framework.Constants
         AccountObtainPetThroughBattle = 157, /*NYI*/ // (Account Only) Obtain a pet through battle
         WinPetBattle = 158, /*NYI*/ // Win a pet battle
         LosePetBattle = 159, /*NYI*/ // Lose a pet battle
-        BattlePetReachLevel = 160, /*NYI*/ // (Account Only) Battle pet has reached level {#Level}
+        BattlePetReachLevel = 160, // (Account Only) Battle pet has reached level {#Level}
         PlayerObtainPetThroughBattle = 161, /*NYI*/ // (Player) Obtain a pet through battle
-        ActivelyEarnPetLevel = 162, /*NYI*/ // (Player) Actively earn level {#Level} with a pet by a player
+        ActivelyEarnPetLevel = 162, // (Player) Actively earn level {#Level} with a pet by a player
         EnterArea = 163, /*NYI*/ // Enter Map Area "{AreaTable}"
         LeaveArea = 164, /*NYI*/ // Leave Map Area "{AreaTable}"
         DefeatDungeonEncounter = 165, /*NYI*/ // Defeat Encounter "{DungeonEncounter}"

Source/Framework/Constants/BattlePetConst.cs

@@ -77,4 +77,12 @@ namespace Framework.Constants
 
         Max
     }
+
+    public enum BattlePetXpSource
+    {
+        PetBattle = 0,
+        SpellEffect = 1,
+
+        Count
+    }
 }