Modified SceneNode::FrustumCull

Now provides an implementation which will test the bounding volume
against the frustum (Basic frustum culling)
Is now const
Disabled face culling on sprites


Former-commit-id: 5cb7a94b38ef8b0ffa5a78f16f5ef65a59ab375d

include/Nazara/Graphics/Model.hpp

@@ -86,7 +86,6 @@ class NAZARA_API NzModel : public NzSceneNode
 		NzModel& operator=(NzModel&& node);
 
 	protected:
-		bool FrustumCull(const NzFrustumf& frustum) override;
 		void InvalidateNode() override;
 		virtual void UpdateBoundingVolume() const;