Create an authentication config object which can be used for communication with a Docker registry
The authentication information is looked up at various places (in this order):
From system properties
From the provided map which can contain key-value pairs
From the openshift settings in ~/.config/kube
From the Maven settings stored typically in ~/.m2/settings.xml
From the Docker settings stored in ~/.docker/config.json
The following properties (prefix with 'docker.') and config key are evaluated:
username: User to authenticate
password: Password to authenticate.