Added Chris Snell's cookbook and a Vagrantfile that creates PostgreSQL servers.

Incorporated a cookbook that Chris created that creates a database user and table space.

Bundled this cookbook with the overall create a PostgreSQL node, and saved into the
Vagrant_single_db_works_out_of_box Vagrantfile. When this VM is launched you should
be able to access it. I modified my Barbican API's barbican-api.conf file to add this
configuration:

sql_connection = postgresql+psycopg2://barbican:<barbican password here>@localhost:5437/barbican_api

Note the non-standard port of 5437, to avoid conflicting with my local PostgreSQL install.
Add Vagrant file to standup a second Postgres node (the slave node).

Both database's stand up, but more is needed to complete the configuration.
For example, this site looks interesting for configuring replication:
http://bartek.im/blog/2012/12/04/postgresql-92-streaming-primer.html