Update .travis.yml
Update .travis.yml

Seems like travis CI does not support R13.
discoproject/disco,discoproject/disco,pombredanne/disco,mozilla/disco,ktkt2009/disco,discoproject/disco,ErikDubbelboer/disco,pombredanne/disco,mozilla/disco,oldmantaiter/disco,oldmantaiter/disco,seabirdzh/disco,mwilliams3/disco,beni55/disco,ErikDubbelboer/disco,oldmantaiter/disco,seabirdzh/disco,mozilla/disco,mwilliams3/disco,simudream/disco,discoproject/disco,beni55/disco,pooya/disco,seabirdzh/disco,pooya/disco,pooya/disco,ktkt2009/disco,simudream/disco,ktkt2009/disco,simudream/disco,mozilla/disco,mwilliams3/disco,pombredanne/disco,pooya/disco,beni55/disco,oldmantaiter/disco,simudream/disco,ktkt2009/disco,beni55/disco,seabirdzh/disco,beni55/disco,ktkt2009/disco,seabirdzh/disco,pombredanne/disco,ErikDubbelboer/disco,discoproject/disco,mwilliams3/disco,simudream/disco,oldmantaiter/disco,ErikDubbelboer/disco,pombredanne/disco,mwilliams3/disco,ErikDubbelboer/disco