Installed devise with user views

* Standard devise setup:
*   Installed devise gem
*   Generated a user model with devise and migrated
*   Generated user views with devise.

* Other small changes to support this setup:
*   Set root route to home#index
*   Created home_controller
*   As recommended by devise, installed simple_form functionality
*   Added index view (not using devise), saying Hello World!
Merge pull request #1 from adwns42/add-devise

Install devise with user views