TIY Week 5, Day 4: User authentication using express-session
Completed June 2017
Using Express, Mustache, and express-session, create an app with a login page. When a user goes to /, and they are not logged in, redirect them to /login/. Upon entering a valid username and password, they should be authenticated and sent back to /. The root page should show that they are logged in and what username they are logged in as.
The valid usernames and passwords should be kept as a data structure in your application.