add cinema_tutorial info

docs/source/gettingstarted.rst

@@ -7,10 +7,16 @@ Cinema is an application-neutral approach to large data analysis, visualization
 
 A good way to get started is to read the `Supercomputing Paper`_ that first described Cinema’s approach. From there, you can move on to reading the specifications, creating databases with our tools, or including Cinema-compliant components in your own workflows.
 
-Video examples, sample data, and viewer downloads are available on the `CinemaScience website`_ .
+Video examples, sample data, and viewer downloads are available on the `CinemaScience website`_.
+
+Interactive Tutorial
+^^^^^^^^^^^^^^^^^^^^
+
+An interactive tutorial can be downloaded from the `cinema_tutorial`_ GitHub page.
 
 .. _Supercomputing Paper : https://datascience.lanl.gov/data/papers/SC14.pdf
 .. _CinemaScience website :  https://cinemascience.github.io/
+.. _cinema_tutorial : https://github.com/cinemascience/cinema_tutorial
 
 .. toctree::
    :maxdepth: 1