Delete enumerations from backend,
repair english level names on frontend;
Add new fields from Employee view;
Refactor controllers;
Merge branch 'develop' of https://github.com/alexey-kozlenkov/ExadelPractice into develop
Delete sorter from frontend controller.
Update file Filter.js
update .gitignore
update .gitignore
Fix bug with feedbacks getForStudent(..).
Merge branch 'develop' of https://github.com/alexey-kozlenkov/ExadelPractice into develop