Changing examples to use makefile

- Testing a modified version of the makefile from raylib Instead of multiple project files for examples.
- Fixed readme example

Examples/models/models_heightmap.cs

@@ -0,0 +1,7 @@
+using Raylib;
+using static Raylib.Raylib;
+
+public partial class Examples
+{
+    /*******************************************************************************************
    *
    *   raylib [models] example - Heightmap loading and drawing
    *
    *   This example has been created using raylib 1.8 (www.raylib.com)
    *   raylib is licensed under an unmodified zlib/libpng license (View raylib.h for details)
    *
    *   Copyright (c) 2015 Ramon Santamaria (@raysan5)
    *
    ********************************************************************************************/
    
    
    public static void Main()
    {
        // Initialization
        //--------------------------------------------------------------------------------------
        int screenWidth = 800;
        int screenHeight = 450;
    
        InitWindow(screenWidth, screenHeight, "raylib [models] example - heightmap loading and drawing");
    
        // Define our custom camera to look into our 3d world
        Camera camera = {{ 18.0f, 16.0f, 18.0f }, { 0.0f, 0.0f, 0.0f }, { 0.0f, 1.0f, 0.0f }, 45.0f, 0 };
    
        Image image = LoadImage("resources/heightmap.png");             // Load heightmap image (RAM)
        Texture2D texture = LoadTextureFromImage(image);                // Convert image to texture (VRAM)
        
        Mesh mesh = GenMeshHeightmap(image, new Vector3( 16, 8, 16 ););    // Generate heightmap mesh (RAM and VRAM)
        Model model = LoadModelFromMesh(mesh);                          // Load model from generated mesh
    
        model.material.maps[MAP_DIFFUSE].texture = texture;             // Set map diffuse texture
        Vector3 mapPosition = { -8.0f, 0.0f, -8.0f };                   // Define model position
    
        UnloadImage(image);                     // Unload heightmap image from RAM, already uploaded to VRAM
        
        SetCameraMode(camera, CAMERA_ORBITAL);  // Set an orbital camera mode
    
        SetTargetFPS(60);                       // Set our game to run at 60 frames-per-second
        //--------------------------------------------------------------------------------------
    
        // Main game loop
        while (!WindowShouldClose())            // Detect window close button or ESC key
        {
            // Update
            //----------------------------------------------------------------------------------
            UpdateCamera(&camera);              // Update camera
            //----------------------------------------------------------------------------------
    
            // Draw
            //----------------------------------------------------------------------------------
            BeginDrawing();
    
                ClearBackground(RAYWHITE);
    
                BeginMode3D(camera);
    
                    DrawModel(model, mapPosition, 1.0f, RED);
    
                    DrawGrid(20, 1.0f);
    
                EndMode3D();
                
                DrawTexture(texture, screenWidth - texture.width - 20, 20, WHITE);
                DrawRectangleLines(screenWidth - texture.width - 20, 20, texture.width, texture.height, GREEN);
    
                DrawFPS(10, 10);
    
            EndDrawing();
            //----------------------------------------------------------------------------------
        }
    
        // De-Initialization
        //--------------------------------------------------------------------------------------
        UnloadTexture(texture);     // Unload texture
        UnloadModel(model);         // Unload model
    
        CloseWindow();              // Close window and OpenGL context
        //--------------------------------------------------------------------------------------
    
        return 0;
    }    
+}