~ Initial SDL2 implementation

Limitation
- Dependent projects need to set NAZARA_PLATFORM_SDL2 if nazara has been build with SDL2 since OpenGL.hpp (and maybe some other headers) exposes platform details
- SDL2 window doesn't supports async window since the API isn't fitting for now
- Contexts parameters can't be changed until we close all the SDL windows (SDL limitation)

src/Nazara/Platform/SDL2/VideoModeImpl.hpp

@@ -0,0 +1,22 @@
+// Copyright (C) 2017 Jérôme Leclercq
+// This file is part of the "Nazara Engine - Platform module"
+// For conditions of distribution and use, see copyright notice in Config.hpp
+
+#pragma once
+
+#ifndef NAZARA_VIDEOMODEIMPL_HPP
+#define NAZARA_VIDEOMODEIMPL_HPP
+
+#include <Nazara/Platform/VideoMode.hpp>
+
+namespace Nz
+{
+	class VideoModeImpl
+	{
+		public:
+			static VideoMode GetDesktopMode();
+			static void GetFullscreenModes(std::vector<VideoMode>& modes);
+	};
+}
+
+#endif // NNAZARA_VIDEOMODEIMPL_HPP