Remove assets group from Gemfile.
Remove vendor/plugins.
Remove mass assignment configuration.
Updated scopes to use lambdas.
Updated with Rails 4 gems and dependencies.
Remove strong_parameters, as it's included in Rails by default.
Remove activeadmin.
Update to Rails 4.

bundle update rails jquery-rails sass-rails coffee-rails uglifier
spork-rails haml-rails squeel simple_form devise
Remove active_admin configuration and implementation.
Added devise secret_key.
Remove deprecated whiny_nils configuration.
Added rails-observers gem, which was removed in 4.x.
Updated to use permanent start/end of string anchors.
Add pry to development and test groups.
Pry belongs in development, not the production group.
Remove the admin section link.
Can't have multiple root routes in Rails 4; using generic routes.
Rails 4 schema update.
Updated rspec to fix "undefined method 'message'" errors.
Set eager_load.