String-valued variables containing spaces can be substituted into an ansible
tasks file but they will not be interpreted correctly.

Updated the default port to reflect MySQL to Postgres change (port 3306 to 5432)

Remove all configuration for MySQL and configure PostgreSQL as the main
database.

All *_mysql_* options have been changed to *_db_* options.

Postgres requires the database user to have a password in order to
connect via localhost. The db_admin_password option is used to set the
password of the admin user (usually postgres).