исправлены ошибки

Рындина 279, мат формула и класс

merge upstream

Updated eslint rules

fixed issue with linting tests

Allow users to update versions of library

Рындина 279, класс и мат.формула

rundina_codwars

Выполнены задачи на codewars Рындина 279

delete codewars/Duplicate Encoder/duplicateEncode.js

delete codewars/Find the missing letter/findMissingLetter.js

delete codewars/Flatten a Nested Map/flattenMap.js

delete codewars/Fun with tree - max sum/maxSum.js

delete codewars/Convert string to camel case/camil_case

delete codewars/Build Tower/towerBuilder.js