Add session routes for login and logout
Generate Sessions: controller, views, helpers, js and css, and test
Fix bug in gravatar_for method, expecting keyword_end
Add link to login
Create login form
Add integration test to avoid persistence of flash messages in login
Add create method
Include SessionsHelper
Add method login to create the session
Add newly created log_in method to create, that way the user is logged in and redirected to his profile page upon session creation
Create current_user method
Add logged_in? method
Require bootstrap
Improve header nav to display custom links depending on user logged_in
Add create method redirect to login, instead of user
Add method User.digest
Add sample user to be able to compare params to create an effective login
Verify login with valid info
Fix bug, unproper indentation
Assert signup redirects to login