JavaScript code refactoring assignment.
Code: https://github.com/johanberonius/kambi-price-calculator/blob/master/src/price-calculator.js
Tests: https://github.com/johanberonius/kambi-price-calculator/blob/master/spec/price-calculator.specs.js
Main page: https://johanberonius.github.io/kambi-price-calculator/
Run tests: https://johanberonius.github.io/kambi-price-calculator/spec/runner.html