Merge pull request #1 from andmcgregor/design

Merge basic design + first feature specs
Make split between posts + projects on index page
Make remaining visitor tests pass
Split Admin::PostsController based on authenticated state
Add environment variabled to application.rb for testing
Add before filter for authentication in Admin::PostsController
Finish writing controller tests for unauthenticated sessions in Admin::PostsController
Fix bug in #check_if_authenticated method
Add SessionsController + routes + #new view
Create SessionsController #create and #destroy actions
Add login form
Refactor Posts#index action
Create tests for SessionsController
Remove temporary env variables from application.rb (put them in tests instead)
Refactor existing controller tests
Fix SessionsController#delete issue by creating /logout route
Fix testing bugs (sessions persisting after tests)
Started integration tests for AdminPosts
Make admin posts integration tests pass
Change #check_if_authenticated method to make more readable