anchor.diff:  
   In many cases it is just required to map a DTO object back and forth. For
   this case, the `SimpleQueryInOutMapperBase` class can be subclassed,
  -which only requires to override two methods:
  +which only requires to override three methods:
   
   [source,java]
   -------------------------------------------------------------------------------
  
positive.code: 
  [source,java]
  ---------------------------------------------------------------------------------------
  public class TxExtension<E> implements TxRepository // this is your extension interface
  {
      @Inject
      private EntityManager em;
  
negative.code: 
  The implementation of the method is done automatically by the CDI
  extension. A client can declare a dependency to the interface only. The
  details on how to use those features are outlined in the following
  chapters.
  
  == Project Setup
  