Add database pod and service for ruby sample app demo

- [x] update ruby-sample-app image with MySQL connection for Sinatra app 
- [x] change docker image URL with OpenShift official image for ruby-sample-app - https://github.com/openshift/ruby-hello-world/pull/5
I have a draft here https://github.com/marianitadn/origin/tree/validate-end-to-end-test once I can run the test again I will test it and cherry pick it here or open a PR to master if we merge this.