README: add assignment writers

README.md

@@ -2,7 +2,7 @@
 
 Java fundamentals through coding exercises.
 
-Contents of this repository are based on [Java programming course material](https://opinto-opas.haaga-helia.fi/course_unit/SWD4TA032) provided by Haaga-Helia University of Applied Sciences.
+Contents of this repository are based on [Java programming course material](https://opinto-opas.haaga-helia.fi/course_unit/SWD4TA032) provided by Haaga-Helia University of Applied Sciences. The original assignments are produced by Teemu Havulinna and Jukka Juslin.
 
 **NOTE**: Assignments and their descriptions are in Finnish for meanwhile. I have a plan to translate them to English.