travis: update go versions
travis: update go versions
rkt/rkt,alban/rkt,joshix/rkt,rkt/rkt,kinvolk/rkt,lucasallan/rkt,rkt/rkt,kinvolk/rkt,lucasallan/rkt,joshix/rkt,alban/rkt,kinvolk/rkt,alban/rkt,joshix/rkt,lucasallan/rkt,coreos/rkt,lucasallan/rkt,rkt/rkt,coreos/rkt,coreos/rkt,kinvolk/rkt,joshix/rkt