Decouple vagrant and ansible

[raghavendra-talur]

Currently ansible playbooks depends on how vagrant sets up the environment. In long term we want to satisfy two modes of development

1. For daily development, we need to have something that can setup a GCS environment on laptops and should be sufficient for a few PersistentVolumes.
2. For larger testing, we need to be able to deploy a bigger GCS environment on nodes already provisioned.

I could see only one reference to vagrant from ansible playbook at line https://github.com/gluster/gcs/blob/master/deploy/vagrant-playbook.yml#L43 If we could remove this coupling it would make it easy to deploy GCS on existing nodes.