xvine: fixes


git-svn-id: https://gnunet.org/svn/gnunet@34150 140774ce-b5e7-0310-ab8b-a85725594a96
Try fixing 3522.


git-svn-id: https://gnunet.org/svn/gnunet@34151 140774ce-b5e7-0310-ab8b-a85725594a96
More fixes for #3522


git-svn-id: https://gnunet.org/svn/gnunet@34152 140774ce-b5e7-0310-ab8b-a85725594a96
Add options for SCALE_FREE topology.


git-svn-id: https://gnunet.org/svn/gnunet@34153 140774ce-b5e7-0310-ab8b-a85725594a96