staging enviroment
del database.yml
fix staging branch
fix app dir
merge develop
Merge branch 'develop' into staging

* develop:
  tmp remove airbrake
igronre idea settings
fix link group to union
divide schedule by union
add breadcrumbs
fix Предагоги
Merge remote-tracking branch 'origin/feature/schedules_for_union' into staging
fix relation
fix relation union-group view
move breadcrumbs into .container
rename Дворец пионеров to Главная
fix breadcrumbs path
Merge branch 'feature/schedules_for_union' into staging
add link to instructors and groups
change h1 to h3