Use bundler cache
Use bundler cache

as described on http://blog.travis-ci.com/2014-12-17-faster-builds-with-container-based-infrastructure/
allspiritseve/aasm,intfrr/aasm,ASnow/aasm,oswaldoferreira/aasm,Funfun/aasm,HoyaBoya/aasm,artofhuman/aasm,xieyunzi/aasm,bilby91/aasm,hspazio/aasm,yui-knk/aasm,Aryk/aasm,aasm/aasm,reidmorrison/aasm,luxola/aasm,pskrz/aasm,awsmsrc/aasm,nickpellant/aasm,joshsoftware/aasm