Update AT.yaml
Update AT.yaml

added Vienna, as names
hexorx/countries,tenforwardconsulting/countries,chargify/countries,HomeStayTravel/countries,burningpony/countries,JuanitoFatas/countries,vcita/countries,aminin/countries,adriagalin/countries,charitywater/countries,touristly/countries,GUI/countries,musicglue/countries,jeffrey410469/countries,xronos-i-am/countries,thieunus/countries,ohenrik/countries,fabn/countries,Savedo/countries