Recipes from sentinel

* `instant_client.sh` installs the prerequisites needed to bundle install the `ruby-oci8` gem in a project ( I renamed it to use snake_case)
* `nginx_source.sh` was changed to allow custom mime types - needed because a project servers `.geojson` and Nginx doesn't associate that extension with `javascript/json` by default
* `nginx_vhosts.sh` allows Nginx to have multiple vhost files - useful for multiple apps - or when you want to run one vhost file for http and another for https
* `postgres.sh` because you need to restart the service for the config changes to take effect
* `postgres_apt.sh` this installs a postgresql package from postgresql.org
* `ssh_access.sh` updates authorized_key file for multiple users (so I can log on as 'jon', 'joe', and 'jane' - and not have to update their `~/.ssh/authorized_keys` files one by one)
* `ssl_certs.sh` copy a keypair to a server so Nginx can serve traffic over https