Sorted CONTRIBUTORS.md alphabetically.

Author: atollk

CONTRIBUTORS.md

@@ -2,15 +2,15 @@
 
 Many thanks to the following developers for contributing to this project:
 
+- [Andreas Tollkötter](https://github.com/atollk)
 - [C. W.](https://github.com/chfw)
 - [Diego Argueta](https://github.com/dargueta)
 - [Geoff Jukes](https://github.com/geoffjukes)
 - [Giampaolo](https://github.com/gpcimino)
 - [Justin Charlong](https://github.com/jcharlong)
 - [Louis Sautier](https://github.com/sbraz)
 - [Martin Larralde](https://github.com/althonos)
+- [Morten Engelhardt Olsen](https://github.com/xoriath)
 - [Nick Henderson](https://github.com/nwh)
 - [Will McGugan](https://github.com/willmcgugan)
 - [Zmej Serow](https://github.com/zmej-serow)
-- [Morten Engelhardt Olsen](https://github.com/xoriath)
-- [Andreas Tollkötter](https://github.com/atollk)