Fix fairshare user duplicities
Fix fairshare user duplicities

 - if user is duplicit, die only if he is in two different groups, in
   other cases take the group instead of root

Laliska/perun-services,CESNET/perun-services,sustr4/perun-services,stavamichal/perun-services,zlamalp/perun-services,CESNET/perun-services,frhrdina/perun-services,stavamichal/perun-services,frhrdina/perun-services,frhrdina/perun-services,sustr4/perun-services,Laliska/perun-services,zlamalp/perun-services,stavamichal/perun-services,stavamichal/perun-services,CESNET/perun-services,Laliska/perun-services,sustr4/perun-services,zlamalp/perun-services,CESNET/perun-services,Laliska/perun-services,sustr4/perun-services,frhrdina/perun-services,zlamalp/perun-services