Updated CHANGELOG message about rails-dom-testing.
Updated CHANGELOG message to include info about rails-html-sanitizer.
Updated Action Pack CHANGELOG with rails-dom-testing info.
Remove some whitespace in actionpack.gemspec.
Remove unneeded comment in test.
Made deprecation messages in sanitize_helper more clear.
Migrated test away from escaped quotes.
Updated testing guide to state the correct instances _element_ can be.
Remove include of rails-dom-testing in rails_info_controller_test.rb as it is included in ActionController::TestCase.