Adds a login_unix_socket option to the postgresql_db module.
Adds a unix_socket/login_unix_socket option to the postgresql_user module.
Adds a login_unix_socket option to the postgresql_privs module.
Merge pull request #43 from drob/postgresql-socket

Adds login_unix_socket options to postgresql modules.
TODO: factor this out into common code as we did for ec2 and others.