Add raytracing in one week-end (#67)

* Add raytracing in one week-end

* Update index.html

Author: ShadowMitia

resources/index.html

@@ -80,13 +80,17 @@
 		## Image-Based Lighting
 		* [The Definitive Weta Digital Guide to IBL](https://www.fxguide.com/fxfeatured/the-definitive-weta-digital-guide-to-ibl/)
 
+		# Raytracing
+		* [Raytracing in one week-end series](https://raytracing.github.io/)
+		
 		# Various Related Resources
 		* [Fix Your Timestep](https://gafferongames.com/post/fix_your_timestep/)
 		* [Finding Your Home in Game Graphics Programming](http://alextardif.com/LearningGraphics.html)
 		* [Game Math](https://gamemath.com/)
 		* [A Comparison of Modern Graphics APIs](https://alain.xyz/blog/comparison-of-modern-graphics-apis)
 		* [Scratchapixel](https://www.scratchapixel.com)
 		* [The Graphics Codex](https://graphicscodex.com/)
+		
 
 	</code>