src/devilry_student/devilry_student/rest/aggregated_groupinfo.py
* Added registration field to decide whether user is a related student
  on the period
src/devilry_student/devilry_student/rest/aggregated_groupinfo.py
* Added attribute "is_registrated" for check on whether a student is
  registrated. Red box warning north in groupview border is shown on
  false condititon.