Update .travis.yml
Update .travis.yml

Turning on travis caching to deal with temperamental artifact repository.
tom-chan/finatra,jaume-pinyol/finatra,jaume-pinyol/finatra,deanh/finatra,tom-chan/finatra,deanh/finatra,nkhuyu/finatra,tempbottle/finatra,tempbottle/finatra,syamantm/finatra,tempbottle/finatra,syamantm/finatra,andrerigon/finatra,twitter/finatra,twitter/finatra,tom-chan/finatra,andrerigon/finatra,nkhuyu/finatra,tempbottle/finatra,deanh/finatra,yonglehou/finatra,syamantm/finatra,andrerigon/finatra,syamantm/finatra,yonglehou/finatra,nkhuyu/finatra,jaume-pinyol/finatra,deanh/finatra,joecwu/finatra,joecwu/finatra,tom-chan/finatra,twitter/finatra,yonglehou/finatra,andrerigon/finatra,nkhuyu/finatra,joecwu/finatra,yonglehou/finatra,jaume-pinyol/finatra,joecwu/finatra