Change gulp-sass to gulp-ruby-sass to support SASS 3.3 features
refactor score to more reusable form
added mock NPM downloads data and mock folder
added d3 dependency and graph class
added a test graph
whitespace fixes, unified JS indentation
made line graph work and improved axis readability
charts: improved x tick logic, removed reduntant logging
graphs: change to ES6 syntax
graphs: apply ES6 syntax