Added Log-in function using Bcrypt

-Added HomeController, which will be the sign up page
-Changed the root route to '/' (home)
-Created a User model
-User model holds the authentication process.
-User/new path added to be the sign up page
-Added routes for users
-Created SessionsController with new, create, and destroy: this will allow us to store session information => log-in and log-out
-Adjusted the routes to fit all the new paths
-Rendered a log-in page at '/log-in'