Rework EnTT integration

- Update EnTT to 3.11.1
- Moved EnTT wrapper to EnTTWorld, inheriting EntityWorld
- AppEntitySystemComponent can now handles multiple EntityWorld
- Headers relying on EnTT are now automatically included if NAZARA_ENTT is defined
- Renamed SystemGraph to EnttSystemGraph (as it depends on it for now)

include/Nazara/Core/AppEntitySystemComponent.inl

@@ -7,37 +7,10 @@
 
 namespace Nz
 {
-	inline AppEntitySystemComponent::AppEntitySystemComponent(ApplicationBase& app) :
-	ApplicationComponent(app),
-	m_systemGraph(m_registry)
-	{
-	}
-
 	template<typename T, typename... Args>
-	T& AppEntitySystemComponent::AddSystem(Args&&... args)
+	T& AppEntitySystemComponent::AddWorld(Args&&... args)
 	{
-		return m_systemGraph.AddSystem<T>(std::forward<Args>(args)...);
-	}
-
-	inline entt::handle AppEntitySystemComponent::CreateEntity()
-	{
-		return entt::handle(m_registry, m_registry.create());
-	}
-
-	inline entt::registry& AppEntitySystemComponent::GetRegistry()
-	{
-		return m_registry;
-	}
-
-	inline const entt::registry& AppEntitySystemComponent::GetRegistry() const
-	{
-		return m_registry;
-	}
-
-	template<typename T>
-	T& AppEntitySystemComponent::GetSystem() const
-	{
-		return m_systemGraph.GetSystem<T>();
+		return static_cast<T&>(*m_worlds.emplace_back(std::make_unique<T>(std::forward<Args>(args)...)));
 	}
 }