Added tests for chapter 9 (profile, admin, users pages)
Added edit and index actions and views on user
Added admin to users table
Added filters for signed_in, signed_out, current_user, admin, delete link in index, and redirecting to original location after signing in
Refactored new and edit pages to use a user_fields partial
Added flash message for sign in, added sample_data.rake, added CSS for users index
Added flash message for user deletion, and a confirm message