add migrations for creating new fields and filling it
improve tests: make factory attributes via generate, change create test
change to parent_full_name and children_name in model and views
change translations
fix showing link to category if it presents
delete unneeded fields
fix in admin part of site
Merge branch 'feature/study_requests_fixes' into develop

* feature/study_requests_fixes:
  fix in admin part of site
  delete unneeded fields
  fix showing link to category if it presents
  change translations
  change to parent_full_name and children_name in model and views
  improve tests: make factory attributes via generate, change create test
  add migrations for creating new fields and filling it