Update to Rails 4
Implement Changes Suggested by RailsCasts

http://railscasts.com/episodes/415-upgrading-to-rails-4
Remove Depcrecated attr_accessible Calls
Get Rails 4 App to Boot
Remove Unused Gem Comment
Fix Failing, More-Specific-Than-Before, Test
Remove Deprecation Warning in Test Run
Resolve Warning Running Web App
Add Heroku-Suggested Production Gem
Ran `rake rails:update:bin`
Merge pull request #25 from pbyrne/rails4

Upgrade to Rails 4