Update contributors list

Author: jfy133

README.md

@@ -161,17 +161,21 @@ Those who have provided conceptual guidance, suggestions, bug reports etc.
 
 * [Alexandre Gilardet](https://github.com/alexandregilardet)
 * Arielle Munters
-* [Charles Plessy](https://github.com/charles-plessy)
 * [Åshild Vågene](https://github.com/ashildv)
+* [Charles Plessy](https://github.com/charles-plessy)
+* [Elina Salmela](https://github.com/esalmela)
 * [Hester van Schalkwyk](https://github.com/hesterjvs)
 * [Ido Bar](https://github.com/IdoBar)
 * [Irina Velsko](https://github.com/ivelsko)
+* [Işın Altınkaya](https://github.com/isinaltinkaya)
 * [Katerine Eaton](https://github.com/ktmeaton)
+* [Katrin Nägele](https://github.com/KathrinNaegele)
 * [Luc Venturini](https://github.com/lucventurini)
 * [Marcel Keller](https://github.com/marcel-keller)
 * [Pierre Lindenbaum](https://github.com/lindenb)
 * [Pontus Skoglund](https://github.com/pontussk)
 * [Raphael Eisenhofer](https://github.com/EisenRa)
+* [Roberta Davidson](https://github.com/roberta-davidson)
 * [Torsten Günter](https://bitbucket.org/tguenther/)
 * [Kevin Lord](https://github.com/lordkev)
 * [He Yu](https://github.com/paulayu)