Add more opengl tutorials (#71)

* Add more opengl tutorials

* Update index.html

Author: ShadowMitia

resources/index.html

@@ -46,6 +46,8 @@
 		* [Guide to Modern OpenGL Functions](https://github.com/fendevel/Guide-to-Modern-OpenGL-Functions)
 		* [Learn OpenGL](https://learnopengl.com/)
 		* [OpenGL 4.6 Specification](https://www.khronos.org/registry/OpenGL/specs/gl/glspec46.core.pdf)
+		* [OpenGL tutorials by Victor Gordan](https://www.youtube.com/playlist?list=PLPaoO-vpZnumdcb4tZc4x5Q-v7CkrQ6M-)
+		* [OGLdev : modern opengl tutorials](https://ogldev.org/)
 
 		## Vulkan
 		* [Fundamentals of the Vulkan Graphics API: Why Rendering a Triangle is Complicated](https://liamhinzman.com/blog/vulkan-fundamentals)