Add transitions gem.
Add simple state machine for validations and actions.
Use rails 4 style confirm popup syntax.
Add carrierwave gem.
Add basic carrierwave upload classes.
Enable file uploads in form.
Don't commit uploaded files.
Remove turbolinks.
Add nested_form gem.
Add nested attachment form to review new and edit.
Add mini_magick gem.
Create thumbnails on upload and show in views.
Add show action.