default void dump(PrintStream out) {
        for (ConfigProducer c : getChildren().values()) {
            out.println("id: " + c.getConfigId());
            if (c.getChildren().size() > 0) {
                c.dump(out);
            }
        }
    }
Dump the tree of config producers to the specified stream.

@param out The stream to print to, e.g. System.out
config-model/src/main/java/com/yahoo/vespa/model/ConfigProducer.java