public static DocumentAccess createForNonContainer() {
        return new MessageBusDocumentAccess();
    }
This is a convenience method to return a document access object when running
outside of a Vespa application container, with all default parameter values.
The client that calls this method is also responsible for shutting the object
down when done. If an error occurred while attempting to create such an object,
this method will throw an exception.
This document access requires new config subscriptions to be set up, which should
be avoided in application containers, but is suitable for, e.g., CLIs.

@return a running document access object with all default configuration
documentapi/src/main/java/com/yahoo/documentapi/DocumentAccess.java