code: public function getConfigTreeBuilder()
      {
          $treeBuilder = new TreeBuilder();
          $rootNode    = $treeBuilder->root('boekkooi_amqp');
  
          $this->addConnections($rootNode);
          $this->addVHosts($rootNode);
          $this->addCommands($rootNode);
          $this->addPublisher($rootNode);
  
          $this->addTactician($rootNode);
  
          return $treeBuilder;
      }
docs: {@inheritDoc}