Fixed per-class thread safety

include/Nazara/Core/StringStream.hpp

@@ -7,14 +7,14 @@
 #ifndef NAZARA_STRINGSTREAM_HPP
 #define NAZARA_STRINGSTREAM_HPP
 
-#define NAZARA_STRINGSTREAM
-
 #include <Nazara/Prerequesites.hpp>
 #include <Nazara/Core/String.hpp>
-#include <Nazara/Core/ThreadSafety.hpp>
 #include <string>
 #include <vector>
 
+#define NAZARA_CLASS_STRINGSTREAM
+#include <Nazara/Core/ThreadSafety.hpp>
+
 class NAZARA_API NzStringStream
 {
 	public:
@@ -51,6 +51,6 @@ class NAZARA_API NzStringStream
 		unsigned int m_bufferSize;
 };
 
-#undef NAZARA_STRINGSTREAM
+#undef NAZARA_CLASS_STRINGSTREAM
 
 #endif // NAZARA_STRINGSTREAM_HPP