Update tutorials.md (#17)

Added the Jupyter notebooks to the haddock3 tutorials

Author: amjjbonvin

src/tutorials.md

@@ -4,8 +4,11 @@ Haddock3 is not only a tool, but also a set of training materials, allowing new
 
 The list of tutorials is available from our [BonvinLab website -> education -> haddock3 -> tutorials](https://www.bonvinlab.org/education/HADDOCK3/)
 
+We have now also added a Jupyter notebooks directory to the source code. Those can be directly started on Google Colab or on your own resource. Visit [https://github.com/haddocking/haddock3/notebooks](https://github.com/haddocking/haddock3/notebooks) for instructions.
+
 Please note that we are constantly adding new tutorials, and therefore new ones may appear from time to time.
 
+
 ## Haddock2.X tutorial
 
 Together with the development of haddock3, we are trying to update and port previously written tutorials made for the haddock2.X series to haddock3.