code: public static JpaModule newServerModule(EntityManager em, TransactionRunner transactionRunner) {
  		return new JpaModule(null, em, transactionRunner);
  	}
docs: Creates a new JpaModule for a Katharsis server. No entities are by
  default exposed as JSON API resources. Make use of
  {@link #addEntityClass(Class)} andd
  {@link #addMappedEntityClass(Class, Class, JpaMapper)} to add resources.
  
  @param em
  to use
  @param transactionRunner
  to use
  @return created module