Made Travis CI automatically deploy to Openshift on success

This PR will allow BrowserQuest to automatically be deployed to Openshift from Travis CI, if the tests pass. The real username and password for the Openshift instance will need to be added to .travis.yml (encrypted, of course).

To encrypt the username and password, you must first install the Travis gem with `gem install travis`. Then, run `travis encrypt USERNAME` and `travis encrypt PASSWORD`. Copy the `secure:` lines to their corresponding place in .travis.yml (removed the dummy text already there).