code: public JodaBeanSer withConverter(StringConvert converter) {
          JodaBeanUtils.notNull(converter, "converter");
          return new JodaBeanSer(indent, newLine, converter, iteratorFactory, shortTypes, deserializers, includeDerived);
      }
docs: Returns a copy of this serializer with the specified string converter.
  <p>
  The default converter can be modified.
  
  @param converter  the converter, not null
  @return a copy of this object with the converter changed, not null