Reorganize source files into logical subdirectories

Co-authored-by: Hirek193 <23196899+Hirek193@users.noreply.github.com>

environment/sky.h

@@ -0,0 +1,29 @@
+/*
+This Source Code Form is subject to the
+terms of the Mozilla Public License, v.
+2.0. If a copy of the MPL was not
+distributed with this file, You can
+obtain one at
+http://mozilla.org/MPL/2.0/.
+*/
+//---------------------------------------------------------------------------
+
+#pragma once
+
+#include "Classes.h"
+
+class TSky {
+
+    friend opengl_renderer;
+    friend opengl33_renderer;
+
+public:
+    TSky() = default;
+
+    void Init();
+
+private:
+    TModel3d *mdCloud { nullptr };
+};
+
+//---------------------------------------------------------------------------