anchor.diff:  Configuration config = ConfigurationProvider.getConfiguration();
   --------------------------------------------
   
  -Hereby the singleton is backed up by an instance of +ConfigurationProviderSpi+.
  +Hereby the +ConfigurationProvider+ singleton is backed up by an instance of +<<ConfigurationProviderSpi>>+.
   
   
   [[PropertyConverter]]
   ==== Property Converters
   
   As illustrated in the previous section, +Configuration+ also to access non String types. Nevertheless internally
  -all properties are strictly is modelled as pure Strings only, so non String types must be derived by converting the
  +all properties are strictly modelled as pure Strings only, so non String types must be derived by converting the
   configured String values into the required target type. This is achieved with the help of +PropertyConverters+:
   
   [source,java]
  
positive.code: }
  --------------------------------------------
  
  
negative.code: [source,java]
  .Interface Configuration in Java 8
  --------------------------------------------
  public interface Configuration{
      // methods also defined in Java 7
      String get(String key);
      <T> T get(String key, Class<T> type);
  