DocumentPropertiesModel, change methods and properties from public to protected, that have not to be visibile from the outside, refs #542
DocumentPropertiesModel, change methods and properties from public to protected, that have not to be visibile from the outside, refs #542

unki/mtlda,unki/mtlda,unki/mtlda,unki/mtlda,unki/mtlda,unki/mtlda