Update index.md

Author: ericelliott

categories/augmented-reality/index.md

@@ -5,6 +5,7 @@
 
 ## Code
 * [W3C AR Community Demos](https://www.w3.org/community/ar/demos-and-projects/)
+* [Tracking.js](https://github.com/eduardolundgren/tracking.js/) Computer vision library with several algorithms to choose from #code
 * [awe.js](https://github.com/buildar/awe.js) Location, Marker, Oculus Rift, Leap, Google Glass, texture mapped projections #code
 * [clmtrackr](https://github.com/auduno/clmtrackr) Facial feature tracking #code
 * [Gest.js](https://github.com/hadimichael/gest.js) Gesture recognition #code