Add MIT Artificial Intelligence course (#2893)

free-courses-en.md

@@ -268,6 +268,7 @@
 * [FindLectures.com](https://www.findlectures.com/?class1=Technology) - Index of conference talks by language / topic
 * [LouvainX Paradigms of Computer Programming – Abstraction and Concurrency](https://www.edx.org/course/paradigms-computer-programming-louvainx-louv1-2x-1#!)
 * [LouvainX Paradigms of Computer Programming – Fundamentals ](https://www.edx.org/course/paradigms-computer-programming-louvainx-louv1-1x-1)
+* [MIT 6.S099: Artificial General Intelligence](https://agi.mit.edu)
 * [MIT Numerical Methods (2014)](http://www.iitg.ernet.in/kartha/CE601-14/CourseSchedule.htm)
 * [MIT's Artificial Intelligence](http://ocw.mit.edu/courses/electrical-engineering-and-computer-science/6-034-artificial-intelligence-fall-2010/)
 * [MIT's Computer Language Engineering](http://ocw.mit.edu/courses/electrical-engineering-and-computer-science/6-035-computer-language-engineering-sma-5502-fall-2005/lecture-notes/)