Merge pull request #484 from phantez/memory

[contributors.md] Add Stéphan Gorget to the contributor list

contributors.md

@@ -104,3 +104,4 @@ Thank you to all contributors:
 * [paulch](https://github.com/paulch)
 * [Nathan Dautenhahn](https://github.com/ndauten)
 * [Sachin Patil](https://github.com/psachin)
+* [Stéphan Gorget](https://github.com/phantez)