Replace mention of comments with notes

Now that there are notes, there are no more comments.

Author: jmbtutor

understanding-git.tex

@@ -1682,7 +1682,7 @@ \section{Conclusion}
     \item[Flight Rules] \href{https://github.com/k88hudson/git-flight-rules}{github.com/k88hudson/git-flight-rules}\\
       Lists commands to use in various situations and why. % Use this to practice visualizing.
     \item[Slide Deck] \href{https://github.com/jmbtutor/understanding-git-slides}{github.com/jmbtutor/understanding-git-slides}\\
-      The source code for this slide deck. There are some additional links in the comments of some slides.
+      The source code for this slide deck. There is a copy with additional notes in the releases.
   \end{description}
 \end{frame}
 \end{document}