This XML file is MDG Technology for GSN. You can create GSN (Goal Structure Notation) model on Enterprise Architect. For detail about GSN, please visit http://www.goalstructuringnotation.info/ .
With this MDG Technology, you can use GSN Diagram, GSN Toolbox, GSN objects and Quicklinker rule for GSN objects. To use this Technology, import the attached file via Specialize Ribbon | Publish-Tech button | Import MDG Technology menu item.
(Update on 15th October 2019: Update text drawings for some objects)