Add bootstrap-sass to project.
Add devise to project.
Include standard Devise setup.
Add a rvmrc
Update schema.rb
Enable token authentication.
Rip out old authentication scheme; fix routes.
Remove useless comments in routes.rb
Do not loop over the flash hash.

There are some flash messages that should not be printed. See:

https://github.com/plataformatec/devise#configuring-controllers
has_secure_password does not play with Devise.
Remove unneeded validations/jiggerypokery in the user model.
Add custom devise views.
Readd show users route.
Remove random gitkeep
Devise now requires it be a proper DELETE request.