add Data Science from Scratch by Joel Grus

courses/free-courses-en.md

@@ -558,7 +558,7 @@
 * [NICO 101 - Introduction to Programming for Big Data](https://github.com/amarallab/Amaral_Lab_Intro_to_Data_Science) - Luis Amaral, Helio Tejedor, Luiz Alves
 * [The Analytics Edge](https://www.edx.org/course/analytics-edge-mitx-15-071x-3)
 * [Time Series Modelling and Analysis](https://www.youtube.com/playlist?list=PL3N9eeOlCrP5cK0QRQxeJd6GrQvhAtpBK) - AIEngineering
-
+* [Data Science from Scratch](https://github.com/joelgrus/data-science-from-scratch) - Joel Grus (GitHub)
 
 ### Databases