docs: update Holiday Extras hiring link

closes #1107

Author: mortonfox

Readme.md

@@ -124,7 +124,7 @@ spend more time on it (ordered by time of contribution):
   video encoding as a service, check it out)
 * [Joyent](http://www.joyent.com/)
 * [pinkbike.com](http://pinkbike.com/)
-* [Holiday Extras](http://www.holidayextras.co.uk/) (they are [hiring](http://join.holidayextras.co.uk/vacancy/software-engineer/))
+* [Holiday Extras](http://www.holidayextras.co.uk/) (they are [hiring](http://join.holidayextras.co.uk/vacancy/software-engineer-5/))
 * [Newscope](http://newscope.com/) (they are [hiring](http://www.newscope.com/stellenangebote))
 
 If you are interested in sponsoring a day or more of my time, please