Added credits file

Author: merenlin

index.html

@@ -198,7 +198,13 @@ <h3>Day 3</h3>
     <li>Data carpentry and machine learning 1,5 hp</li>
   </ul>
 
-  Getting the course certificates requires completing all the workshop assignments.
+  Getting the course certificates requires completing all the workshop assignments and getting 
+  them accepted by one of the instructors at any time during the workshop. 
+
+  If you are not registered at SU, please provide your personal number in this file (will be open
+  for editing until 15:30 2 Dec):
+  <a href="https://docs.google.com/spreadsheets/d/1HJ4ZuRYvzl6XxPGmccZsiuDkMTQ7J5OCPee9vFP1hEQ/edit?usp=sharing">Credits file</a>
+
   </p>
 </div>