add ruby version to travis config
add ruby version to travis config

AWildColin/bike_index,AWildColin/bike_index,bikeindex/bike_index,Loos/bike_index,bikeindex/bike_index,realchrisolin/bike_index,realchrisolin/bike_index,Loos/bike_index,Loos/bike_index,bikeindex/bike_index,realchrisolin/bike_index,realchrisolin/bike_index,bikeindex/bike_index,AWildColin/bike_index