FeaturesController#update_all: pass model errors to translation
FeaturesHelper: add arturo_flash_messages helper
Views: use arturo_flash_messages helper
FeaturesHelper: require 'action_view'

https://travis-ci.org/jamesarosen/arturo/jobs/5747404 is failing when
trying to automatically load TagHelper. I can't replicate this locally,
even on the same Ruby, RubyGems, and RVM. My first hypothesis is that
loading action_view will cause the proper dependencies to be loaded.
Gemfile: use rubygems.org directly as source
Merge pull request #41 from jamesarosen/message_cleanup

Message cleanup