- refactoring, extracting embedded classes to own files

.../dps/repository/plugin/SLUBXmlFormatValidationPlugin.java

...etta/dps/repository/plugin/ValidationCatalogResolver.java

...rosetta/dps/repository/plugin/ValidationErrorHandler.java

.../slub/rosetta/dps/repository/plugin/validationSchema.java

...org/slub/rosetta/dps/repository/plugin/xmlInfoRecord.java