Add python3 test
Add python3 test

open() has no encoding keyword argument in python2

wger-project/wger,DeveloperMal/wger,kjagoo/wger_stark,rolandgeider/wger,DeveloperMal/wger,wger-project/wger,petervanderdoes/wger,wger-project/wger,rolandgeider/wger,rolandgeider/wger,rolandgeider/wger,kjagoo/wger_stark,DeveloperMal/wger,kjagoo/wger_stark,DeveloperMal/wger,petervanderdoes/wger,petervanderdoes/wger,petervanderdoes/wger,kjagoo/wger_stark,wger-project/wger