Fixed problem in the init script

This is https://github.com/travis-ci/travis-cookbooks/pull/134

My master branch of this repo contains lots of other changes, I've basically rewritten almost all of it. Partly because I needed to understand things, partly because it didn't work with C* 1.2 and partly because I wanted it to work in CentOS. Perhaps we can make something together that would work in both Ubuntu and CentOS? I'm not a chef expert.