activate layout links for login and logout, add routes
Create Sessions Controller and login form view

also rename new session route as login
Add simple login feature test
Add authorisation filters to controllers

checking for current_user before loading any user views
update static pages layout to show flash messages
update link to login form
update tests so that sessions exist before any actions
remove view specs
remove unused static pages helper test
Merge pull request #4 from jonnyparris/sessions

Sessions