Add real questions from resources

[pbmasigla]

Cracking the Code - halfway. answers needed still.
https://github.com/h5bp/Front-end-Developer-Interview-Questions
https://github.com/khan4019/front-end-Interview-Questions
https://github.com/andyshora/front-end-interview-questions
https://github.com/shikolay/Front-end-Developer-Interview-Answers