Split error macro into two versions (format vs non-formating) to allow format checking at compile-time

src/Nazara/Network/UdpSocket.cpp

@@ -275,7 +275,7 @@ namespace Nz
 		if (!ptr)
 		{
 			m_lastError = SocketError::Packet;
-			NazaraError("Failed to prepare packet");
+			NazaraError("failed to prepare packet");
 			return false;
 		}