generated the Sessions controller and integration test for authentication pages
initial test for the signin page
added sessions resource and routes
created the new, create and destroy actions
initial version of the signin page
initial tests for sign in failure
initial tests for sign in success
created the signin form
tests for flash persistence bug after authentication failure
code to handle signin failure
complete sessions controller create action
included SessionsHelper in all controllers
migration to add remember token to users model
tests for a valid(non-blank) remember token
added a before_create callback to create remember_token
complete (but not-yet-working) sign_in function
defined assignment to current_user.
code to find current_user using the remember token
added the signed_in? helper method
changed the layout links for signed-in users