Upgrade to Rails 4

* Update related gems
* Update asset urls to use image-url and font-url helpers
* Require 'rails/all' in config/application.rb
* Use rails-recommended binstubs strategy
* Use github jasminerice version
* Update aws_sdk back to 1.3.9
* Source of factory girl problem: encryptor
* Add encryption key env variable
* Add ENV['HOSTNAME']
* Remove allow_mass_assignment matchers
* Strong paramters enforces
* Remove mass_assignment shoulda matchers
* Save hashie:mash as string before saving as extra
* Extra is reponse.to_s
* Update sessions controller to fresh yammer user data
* Build stubbed instead of build because build creates a suggestion
* Add jquery-ui gem
* Remove deprecated bourbon mixin of border-radius
* Remove depreacted 'auto_explain' config
* Add normalize css
* Go back to old version of bourbon
* Update bourbon
* Update step definition to include hover
Reference zclip for mindstems/zvlip-rails