added omniauth and facebook gem and run bundle install
Generated migrations and models
in app/models/identity.rb added validation and method to connect facebook to identity
added omniauth for facebook, added key and secret in app/config/initializers/devise.rb
added code in config/environments/production.rb, maybe you need to add the same code in deployment
added routing for facebook in routes.rb
added omniauth_callbacks_controller.rb so that i can verify that a user is not already created
added :omniauthable in models/user.rb, that fixed a bug, also made sure there was only one devise_for :users instance in routes.rb
 added code in models/user.rb
added code in routes.rb that
added controllers/user_controller.rb
added the folder users under views, it can be a future problem if this needs to be created by a acaffold, inside users i creates finish_signup.html.erb and added some code, need to link this page in routing later
added the method ensure_signup_complete in controllers/application_controller.rb
facebook login does now work!!
adding files from faceboklogin branch with a merge