* feat(lint): add php-cs-fixer for linting
Removing previous CODE_STYLE as it was not enforced anyway and using PER-CS 2.0.
This is not the reformatting commit.
* style: format code according to PER-CS 2.0 with php-cs-fixer
* ci(actions): add lint action
Resolves#1132.
* New feature: users can rate support answers
Now users can rate support answers. They will see links "This is good answer" and "This is bad answer", like it was in original VK.
