Address tests failures under Rails 4.2.0.beta1 - 

Failing in travis with this: deprecated_sanitizer/version.rb:1:in `<top (required)>': Rails is not a module (TypeError) (https://travis-ci.org/collectiveidea/delayed_job/jobs/33634692)

This pull request: https://github.com/rails/rails-deprecated_sanitizer/pull/1 needs to be released as well for the tests to run, at which point, there is one failure.