Add TurnStart, TurnEnd and ExperienceGain event triggers.

Signed-off-by: Deukhoofd <Deukhoofd@gmail.com>

src/Battling/Models/Creature.cpp

@@ -213,6 +213,9 @@ void Battling::Creature::AddExperience(uint32_t amount) {
     if (level >= maxLevel) {
         exp = _library->GetGrowthRateLibrary()->CalculateExperience(this->GetSpecies()->GetGrowthRate(), maxLevel);
     }
+    if (_battle != nullptr) {
+        _battle->TriggerEventListener<ExperienceGainEvent>(this, _experience, exp);
+    }
     _experience = exp;
     _level = level;
 }