Renderer/Renderer: Replace listeners by signals

Former-commit-id: c1293f7f7cc31c4122ba866fc44d93188917ad93

include/Nazara/Utility/IndexBuffer.hpp

@@ -10,6 +10,7 @@
 #include <Nazara/Prerequesites.hpp>
 #include <Nazara/Core/ObjectListenerWrapper.hpp>
 #include <Nazara/Core/ObjectRef.hpp>
+#include <Nazara/Core/Signal.hpp>
 #include <Nazara/Utility/Buffer.hpp>
 
 class NzIndexBuffer;
@@ -66,6 +67,8 @@ class NAZARA_API NzIndexBuffer : public NzRefCounted
 
 		template<typename... Args> static NzIndexBufferRef New(Args&&... args);
 
+		NazaraSignal(OnIndexBufferRelease, const NzIndexBuffer*); //< me
+
 	private:
 		NzBufferRef m_buffer;
 		bool m_largeIndices;